Rats Of Different Sex Research Articles

Features of liver structural organization in posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) is a severe psychological condition resulting from traumatic experiences, leading to long-term physiological changes in the body. It affects mental health and induces hormonal imbalances that disrupt the hypothalamus-pituitary-adrenal axis, influencing multiple organ systems. While PTSD is often linked with comorbid conditions like depression and anxiety, its effects on the hepatobiliary system are less understood. Aim. This study aimed to assess PTSD's impact on liver morphology in rats of different sexes and compare the severity of changes between males and females, contributing to the understanding of stress-related physiological effects. Materials and Methods. The experiment involved 40 Wistar rats, divided into control and PTSD-induced groups for both sexes. A validated stress induction protocol was used, followed by a thorough morphological analysis of liver specimens fixed in 10% formalin and stained with hematoxylin-eosin. Histopathological evaluation focused on liver architecture, hepatocyte condition, vascular integrity, and cellular organization. Results. Control animals displayed standard liver structure, while PTSD-induced groups exhibited significant morphological changes, such as dystrophic alterations in hepatocytes, congestion in hepatic veins, and the formation of blood clots. Female rats showed more pronounced changes than males, including hepatocyte swelling and vacuolization, indicating heightened cellular stress and reduced regenerative capacity. Conclusions. The findings highlight that PTSD-related liver changes were more significant in female rats, emphasizing the importance of considering gender differences in stress-related disorders. These alterations suggest a complex interaction between chronic psychological stress and liver physiology, warranting further research on mechanisms by which PTSD affects the hepatobiliary system and potential therapeutic interventions. for at-risk populations.

МОРФОЛОГИЧЕСКАЯ ХАРАКТЕРИСТИКА ПРЕПУЦИАЛЬНЫХ И КЛИТОРАЛЬНЫХ ЖЕЛЕЗ У ДЕКОРАТИВНЫХ КРЫС

The aim of the study is to investigate the structural features of the preputial glands of males and clitoral glands of females in clinically healthy adult sexually mature pet rats. The object of the study is pet rats kept by private owners in the city of Krasnoyarsk and the Krasnoyarsk Region, which died from various disea¬ses not associated with pathologies of the studied glands. The material of the study was the clitoral and preputial glands collected from the corpses of dead animals during pathological examination. The material from 13 females weighing from 248 to 567 g and 11 males weighing from 229 to 720 g was studied. The age of the animals ranged from 12 to 36 months. The preputial and clitoral glands are paired organs of external secretion, located in the thickness of the subcutaneous fat, and are well developed in animals of both sexes. Their absolute weight significantly differs between rats of different sexes and is (0.22 ± 0.02) g in males and (0.14 ± 0.01) g in females (P ≤ 0.01). The relative mass of the glands in animals of both sexes is (0.4 ± 0.01) % of the body mass. It has been established that the preputial glands in males and the clitoral glands in females of pet rats have a comparable histological structure. According to the type of secretion, they are holocrine, according to the characteristics of the excretory ducts, they are branched, and according to the shape of the terminal sections, they are alveolar. They produce a pasty secretion, which has a color from yellowish to light brown, contains a large amount of lipids and has a pungent odor.

Development of oxidative stress in rats of different sexes subjected to immobilization stress of different durations

Introduction. The problem of stress is currently one of the main problems not only in Ukraine, but also in the whole world. True, stress does not lead to damage in everyone, some adapt to stress. Studying the impact of different durations of stress, in particular, clarifying the mechanisms of their impact on the body, is relevant. The purpose of the study is to evaluate the processes of lipid peroxidation in the blood of rats of different sexes that have experienced stress of different durations. Materials and methods. Experiments were performed on 56 white male Wistar rats aged 3.5-4 months. The animals were divided into 4 groups: 1 – control, 2 – stress during 1 hour (Stress 1), 3 – stress during 2 hours (Stress 2), 4 – stress during 3 hours (Stress 3). Stress was induced by gently fixing the animal's on a plate with its back down. Superoxide dismutase and catalase activity (SOD, CAT), the concentration of diene and triene conjugates (DC, TC), Schiff's bases (SB), TBA-active products (TBA-ap) were determined in blood serum. Research results and their discussion. In male rats with Stress 1, compared to the control, there was an increase of DC by 11.1%, TC – by 14.9%, SB – by 26.3%, TBA-ap – by 27.5%, SOD – by 12.5%, CAT – by 31.3%. In female rats with Stress 1, compared to the control, there was an increase in DC by 4.2%, TC – by 8.9%, SB – by 45.2%, TBA-ap – by 14.1%, SOD – by 15.5%, and CAT – by 7.3%. Such results indicated greater activation of lipid peroxidation processes in males and greater activation of antioxidants in females. In males with Stress 2, compared to the control, the content of DC increased by 83.1%, TC – by 97.4%, SB – by 65.1%, TBA-ap – by 2.6 times, SOD decreased by 9.5%, CAT increased by 44.5%. In females with Stress 2 the content of DC increased by 30.3%, TC – by 28.2%, SB – by 35.5%, TBA-ap – by 85.6%. SOD was at the same level as in the control, CAT increased by 23.1%. Such results indicated a greater activation of lipid peroxidation processes in males and a decrease in their antioxidant activity. In males with Stress 3, compared to the control, the content of DC increased by 2.6 times, TC – by 2.8 times, SB – by 75.8%, TBA-ap – by 3.2 times. SOD decreased sharply by 41.9%, and CAT increased by 66.6%. In females with Stress 3 the content of DC increased by 2.5 times, TC – by 2.5 times, SB – by 45.2%, TBC-ap – by 2.9 times. SOD sharply decreased by 19.6%, and CAT increased by 35.4%. Such results indicated a significant activation of lipid peroxidation processes when antioxidant activity was depleted in males. It was also noted the presence of erosions on the mucous membrane precisely during stress lasting 3 hours, when spot hemorrhages appeared after 2 hours, and hyperemia of the gastric mucosa - after 1 hour. Conclusion. Animals adapt to stress lasting 1 hour. With stress that lasts for 2 hours, disadaptation of animals occurs. With stress that lasts for 3 hours, the animal's body becomes exhausted. In male rats, lipid peroxidation processes occur at a higher level, compared to females.

Age- and sex-related dynamics of structural and functional motor behavior interactions in striatum neurons in rats

Aim. To study the age-related dynamics of structural and functional interactions of striatal neurons in the implementation of acts of motor behaviour in rats of both sexes.Materials and methods. The study was carried out on 36 Wistar rats of both sexes aged 2, 7 and 16 months (n = 6 per group). In animals of all groups, locomotor activity was determined using a Laboras device (Metris, the Netherlands) for15 minutes, after which the brain was sampled to determine the number and size of neurons in the striatum. The median and interquartile range of the index of motor activity and the number of neurons were determined, and to study the relationship between these indicators, a correlation and regression analysis was performed with the construction of linear and polynomial trends, and the coefficient of determination R2 was calculated.Results. The size of neurons did not change significantly with age in the rats of both sexes. The number of neurons differed statistically in the rats of different sexes in all age groups. In male rats, the maximum number of neurons was noted at the age of 7 months with a decrease to 16 months. In female rats, the maximum number of neurons was recorded at the age of 2 months with a further decrease to 7 and 16 months. According to the regression analysis, a linear strong relationship (R2 =0.80 for males, R2 = 0.79 for females) was established between the number of neurons in the striatum and motor activity in 2-month-old animals. At the age of 7 and 16 months the relationship is non-linear.Conclusion. The number of neurons in the striatum is subject to sex and age dynamics, while their size remains unchanged from 2 to 16 months. For animals of both sexes, a decrease in the role of the striatum in providing motor activity in the process of growing up was noted. This relationship reaches its maximum in 2-month-old rats and then decreases.

Zoning of the reaction of the tissues of the implantation area after prosthetic repair in abdominal hernias in experiment

Purpose of the study. Development of criteria for evaluating the reaction of tissues in the implantation area after prosthetic repair of the hernia ring in an experiment using new digital image processing technologies.Materials and methods. The experiment was carried out on 13 Wistar rats of different sexes. Under anesthesia, a 4 × 2 cm mesh prosthesis was implanted in the layer similar to the onlay epiaponeurotic. The preparation and staining of each preparation was carried out in two versions: with hematoxylin-eosin and according to Mallory on different glasses. The seasons for performing experiments are winter, summer. Microphotography was performed on a medical transmitted light microvisor Microvisor μVizo‑103 (AD LOMO, Russia) with a 3.2 Mpx matrix (full frame size 1024 × 882 px, infoband width 88 px) with Planachromat and Stigachromat lenses with a digital scale × 1 (i.e. no digital zoom). Microphoto processing was performed using the ImageJ 1.53k program (version for public use). The criterion for including a microphoto in the calculation of indicators was the presence of an ingrown implant fiber in the preparation or a cavity surrounding the implant.Results. The zone adjacent to the implant, with a width of about 50 µm ("the zone of changes in adjacent tissues") significantly differs from the "zone of changes in distant tissues" by a more pronounced inflammatory reaction due to a larger absolute number of lymphocytes (р = 0.019 and fibroblasts (р = 0.017), giant cells of foreign bodies (р < 0.001), larger vascular area (р < 0.001) and extravasations (р = 0.002). The study of the "zone of changes in adjacent tissues" is of key importance in assessing the local response of the body to implantation. The key zones of the implantation area are identified: "the cavity surrounding the implant", "the zone of changes in adjacent tissues", "the zone of changes in distant tissues". The calculation of indicators within these zones allows you to get more detailed results when comparing study groups in the experiment.Conclusion. An effective method for assessing the reaction of tissues in the implantation area after prosthetic hernia repair in an experiment using new digital imaging technologies that can be used using a conventional optical microscope and standard staining methods is proposed.

Morphological signs of the prophylactic effect of 1,3-diethylbenzimidazolium triiodide on the ectopic growth of sarcoma 45 in the lung

Purpose of the study. An analysis of morphological features of the lung sarcoma 45 ectopic growth in rats of different sexes in course of experimental therapy with 1,3‑diethylbenzimidazolium triiodide.Materials and methods. Studies were carried out on 60 white nonlinear female and male rats weighing 180–220 g with transfusion of sarcoma cells 45 suspension from the subclavian vein into the lung, which resulted in subsequent ectopic tumor growth. At the same time, per os, 0.5 ml of an aqueous solution of 1,3‑diethylbenzimidazolium triiodide in a single dose of 0.4 mg/kg was administered. Morphological control of the lung tumor growth was carried out in stages, weeks 1 through 8, while assessing visual changes with Axiovert microscope (Carl 44 Zeiss, Germany) as well as with Axiovision 4 image visualization program (Carl Zeiss, Germany).Results. It was found out that, instead of the initial acute phase of blood flow reduction due to introduction of tumor cells resulting in neoplastic growth, activation of the immunity cellular link occurred under the influence of 1,3‑diethylbenzimidazolium triiodide along with a compensatory increase in bronchoalveolar structures, regression of tumor nodes and proliferation of connective tissue. At the same time, in females, a more rapid restructuring of the protective cellular systems of the lung occurs, and tumor regression is observed.Conclusion. The morphological manifestations of triiodide indicate the antitumor effect of 1,3‑diethylbenzimidazolium on the possibility of inhibiting lung sarcoma 45 ectopic growth and demonstrate a high reactivity of female rats to the damaging effect of the tumor and the rate of disturbed pulmonary structures compensation.

Interleukins changes in blood of non-ethanol liver damage rats of different sex

Non-alcoholic liver disease is associated with liver injury, such as steatosis, steatohepatitis, fibrosis and cirrhosis. During their development, inflammation is occure and organs damage develops by help of cytokines influences. The intensity of injury depends on sex. The aim of the study was to evaluate changes of interleukins in the blood of male and female rats with hepatosis, hepatitis used by overdrinking of glucose. Material and methods of investigation. The experiments were performed on 60 male and 60 female outbred rats aged from four monthes (start of experiment). Animals were divided into five groups – control 1 (6 monthes old animals), control 2 (8 monthes old animals), glucose 2 monthes (3), glucose 4 monthes (4), and glucose 2+2 monthes (5). Determined in the blood serum Tumor Necrosis Factor Alpha (TNF-α), Interleukin 1 Beta (IL-1β), Interleukin 4 (IL-4), Interleukin 10 (IL-10). Results. In 3, 4 and 5 groups we determined increasing of proinflammatory interleukins. When comparing the results of 5 groups with 3 in male rats, lower values of anti-inflammatory interleukins were noted with a reliably insignificant difference in the content of pro-inflammatory interleukins. Interleukins changes were not detected in rats female between groups 5 and 3.When comparing 3 and 4 groups, an increase in TNF-α and IL-1β, a decrease in IL-4 and IL-10 both in males and in females were determing, which depended on the duration of glucose consumption. When comparing groups 5 and 4 in males rats, only TNF-α decreased, which can be regarded as a decrease in destructive processes when glucose consumption is stopped. In females, we see a decrease in TNF-α and IL-1β, an increase in IL-4 and IL-10, which may indicate a decrease in the effect of glucose or its long-term effect, since the results of groups 3 and 5 in female rats did not differ. Conclusion. An increase in the content of pro-inflammatory interleukins and a decrease in anti-inflammatory interleukins was detected after 2 months, 4 months of glucose use, which is maintained for 2 months after the cessation of its use only 2 months and depends on the duration of glucose use. In males, the inflammatory reaction is more than in females.

Free radical processes in rat liver in experimental diabetes, malignant growth and their combination

Purpose of the study. To study the intensity of lipid peroxidation (LPO) and indicators of antioxidant protection in the liver of rats of different sexes with combined pathology – the growth of Guerin's carcinoma in presence of experimental type 1 diabetes mellitus.Materials and methods. The levels of malondialdehyde (MDA) and diene conjugates (DC), the activities of superoxide dismutase (SOD) and catalase, and the levels of vitamins A and D were studied by conventional spectrophotometric methods in liver tissue samples from males and females with alloxan‑induced diabetes mellitus (DM), transplanted Guerin’s carcinoma (GC) and in animals with combined pathologies (GC growth in presence of diabetes mellitus), as well as in intact rats.Results. The levels of both LPO markers in intact females were significantly higher than in males: MDA by 3 times, DC by 2 times. The development of DM led to an increase in the content of MDA and DC in the liver of males compared with intact animals, which indicated an intensification of LPO. At the same time, there was an almost twofold increase in SOD activity, a decrease in catalase activity, and an increase in the ratio of enzymes by 2.8 times. In females, there was no increase in LPO in the liver; there was only a less pronounced increase in SOD activity than in males. At the same time, SOD activity in males was 37 % higher than in females, and catalase activity, on the contrary, was lower by 33 %, which caused a twofold excess of the ratio of enzymes in males relative to females. Among animals with GC, only males had an increase in SOD by 2.5 times, a decrease in catalase activity, and an increase in the SOD/Catalase ratio by 3 times relative to intact animals, which may be due to pronounced sex differences the SOD activity and SOD/Catalase ratio in males were 3–4 times higher than that of females. The levels of MDA and DC in males with GC growing in presence of DM remained elevated, although to a somewhat lesser extent than in DM alone, while in females both indicators were reduced. The ratio of vitamins E and A increased only in males. SOD activity and SOD/Catalase coefficient in animals of both sexes with combined pathologies were significantly lower than in groups with only DM or GC.Conclusions. The data showed that diabetes mellitus changes the specificity of oncogenesis depending on the sex of the animals. Males with the growth of Guerin's carcinoma in presence of diabetes in conditions of inhibition of SOD activity and a decrease in the ratio of conjugated enzymes of the first line of antioxidant defense demonstrate an intensification of LPO accompanied by an increase in the non‑enzymatic unit of the antioxidant system, while there is no increase in LPO in females, and the indicators of antioxidant activity change to a lesser extent.

FEATURES OF SKIN MICROCIRCULATION IN RATS OF DIFFERENT SEX AND AGE

Purpose. Investigate the parameters of skin microcirculation of rats of different sex and age by laser Doppler flowmetry.
 Materials and methods. The study was conducted on 60 mongrel rats of both sexes weighing 120-270 g. The first group included 20 rats aged 1 month, the second – 20 rats aged 6-12 months and the third – 20 rats aged more than 18-24 months. Microcirculation was studied using a laser Doppler flowmeter with zoletil-xylazine anesthesia on the skin of the anterior abdominal wall. Statistical analysis was performed using the application package Statistica 13.0 (StatSoft, USA).
 Results. The microcirculation index was slightly higher in males than in females rats in the skin of the animals’ abdomen. In the 1st age group, this difference was 8.96% (R=-0.27), in the 2nd - 4.19% (R=0.09), in the 3rd – 0.62% (R=-0.13). The myogenic tone index was consistently lower in males than in females – by 59.73% in 1st (R=0.12), by 9.86% in 2nd (R=0.20) and by 8.84% (R=0.46) in the 3rd age group. The microcirculation index was decreased by 11.15% (R=0.75) between 1st and 2nd age groups, by 39.04% (R=0.29) between 1st and 3rd age groups. The index ϭ (variable component of the microcirculation index) was increased in animals of the 2nd and 3rd groups. It indicated the preservation of the mechanisms of modulation of cutaneous blood flow in aged animals.
 Conclusion. There was no statistically significant dependence of the microcirculation index in the skin of the abdomen on the sex of the animals. The basic parameters of microcirculation and the amplitude-frequency spectrum were decreased in aged animals.

EFFECT OF PRENATAL STRESS ON NOC CEPTIVE SENSITIVITY OF MALE AND FEMALE RATS AT DIFFERENT PERIODS 173 OF POSTEMBRYONIC DEVELOPMENT

A change of pain sensitivity in rats of different sex and age (21st day, suckling period; 30th day, infantile period; and 60th day, juvenile period) was studied after prenatal stress of forced swimming in cold water. The perceptual component of nociception in prenatally stressed animals was shown to decrease on the 60th day of life compared to that in 21-day-old specimens. Importantly, the intensity of pain perception in juvenile rats subjected to intrauterine stress was smaller than control specimens. After prenatal stress, the emotional component of nociception in juvenile males and females was lower than in younger specimens. Therefore, prenatal stress is accompanied by a decrease in the perceptual and emotional components of nociception during the juvenile period, but not at the earlier stages of postembryonic development. The observed fluctuations in the degree of perception of the pain stimulus in male animals are slightly greater than those in females.

Study of possible sex features of ramipril and candesartan treatment under experimental arterial hypertension in rats

The article presents the results of a preclinical study of ramipril and candesartan in an experimental group of hypertensive rats of different sexes. Antihypertensive therapy was performed for 21 days. The drugs were administered daily in moderate therapeutic doses calculated for rats using the coefficient of species sensitivity. It was found that the course of experimental hypertension has gender differences, and in males, according to blood pressure, the level of NO metabolites is more pronounced. The use of ramipril from the group of ACE inhibitors and candesartan from the ARBs group in experimental hypertension in rats has gender differences. Ramipril is likely to be more effective in normalizing blood pressure and endothelial function in males than females. The use of candesartan did not show significant gender differences, but there was a tendency for females to be slightly more effective than males. Established gender differences in hypertension pharmacotherapy should be considered to optimize treatment.

Comparative study of specific activity of rectal suppositories with clopidogrel

One of the most effective platelet antiaggregants is clopidogrel, inhibiting platelet activation by selectively binding adenosine diphosphate (ADP) with specific receptors. However, in a number of clinical situations it is necessary to have a pronounced antithrombotic effect in the shortest possible time which gives rise to interest in the transmucose use of the drug, in particular, rectal route. The theoretical preconditions for the development of a rectal administration of clopidogrel are based on the data that the anti-aggregation effect of a substance is carried out by its main metabolite formed after “first hepatic passage”, while clopidogrel itself in this aspect is inactive. On the base of complex physico-chemical, pharmaceutical, biopharmaceutical, rheological and microbiological investigations, the rational composition of clopidogrel rectal dosage form – suppository on a hydrophilic base to prevent atherothrombotic events in patients with myocardial infarction, acute coronary syndrome, ischemic stroke, peripheral arterial occlusion, is proposed by the employees of the Department of Technology of Medications of the Zaporizhzhia State Medical University. The aim of the work is to investigate the specific activity of rectal suppositories with clopidogrel. Materials and methods. Experimental suppositories with clopidogrel 0,075 g for rectal administration were used as the objects in pre-line studies. The ability of clopidogrel to reduce the inhibitory effect of ADP on adenylate cyclase activity and decrease the number of binding sites for 2-methylthio-ADP (analogue of ADP) without altering the receptor topography is used as a base of the method of comparative study of its specific activity in the rectal dosage form (suppository) and in comparison with the reference medication Plavix (SANOFI WINTHROP INDUSTRIE, France) in the tablet form. Studies were performed on white non-linear rats of different sexes with different mass 150–210 g, aged 3.5–5.0 months. Results. Statistically significant differences in the inhibition of induced platelet aggregation were registered after 6 hours of rectal administration of clopidogrel and gastric administration of the reference medication, indicating the effectiveness of the rectal applicative transmucosal route for this active pharmaceutical ingredient (API). On the 5th day of administration, inhibition of induced platelet aggregation significantly increased, and that is supported by literature on the cumulative effect of clopidogrel in daily life. When comparing the digital material of the table, it is obvious that the rectal administration of clopidogrel is more effective in comparison with oral route which is probably due to the rapid delivery of API to the liver and the formation of an active metabolite of clopidogrel inhibiting the induction and spontaneous aggregation of platelets in human’s and animal’s blood. Obtained data provide with sound arguments for development of rectal suppositories with clopidogrel because in clinical care faster achievement of an anti-aggregation effect in patients with acute coronary syndrome is the primary task of clinical pharmacology and pharmacy. Conclusions. Using the biochemical model of pathology, it was established that the applicative semisolid medication of clopidogrel in the form of rectal suppository exhibited inductive anti-aggregation activity and its administration didn’t reveal any side effects and undesirable events. Rectal suppositories with clopidogrel have been shown to exhibit faster reliable anti-aggregation effect in comparison with intragastric administration.

Визначення рівня мелатоніну у щурів різної статі та віку при виразковому ураженні шлунка

Метою дослідження було визначення рівня мелатоніну в сироватці крові у щурів різної статі та віку при виразковому ураженні шлунка. Матеріали та методи. Методом спирто-преднізолонового ушкодження моделювали виразкове ураження шлунка та за допомогою імуноферментного аналізу визначали рівні мелатоніну в сироватці крові у щурів різної статі, які були розподілені на групи за віком, а саме — 3, 9, 15 та 20 міс., що відповідає віку людини 14, 29–30, 43–44, 55–56 років відповідно. Результати. Встановлено, що на тлі виразкового ураження шлунка відбувається вірогідне зниження рівня мелатоніну як у самців, так і у самок у всіх вікових групах. Відносно групи контролю у щурів-самців найбільше зниження відбулося у тварин віком 9 та 20 міс. — на 39 та 43 % відповідно (р ≤ 0,05). У самок на тлі виразкового ураження шлунка зниження рівня мелатоніну відносно групи контролю було на 21–23 % (р ≤ 0,05). Обговорення. Отримані результати свідчать, що виразкове ураження шлунка, ймовірно, призводить до пошкодження ентерохромафінних клітин слизової оболонки шлунка, що супроводжується вірогідними зниженнями рівнів мелатоніну у щурів обох статей і всіх вікових груп, та дозволяють припустити, що саме у чоловіків віком 29–30 та 55–56 років виразкове ураження призводить до значного пошкодження екстрапінеальних джерел синтезу мелатоніну та більш тяжкого перебігу виразкової хвороби з розвитком ускладнень. Висновки. Таким чином, виразкове ураження шлунка призводить до зниження рівнів мелатоніну в сироватці крові у щурів різної статі та віку. Найбільше зниження рівнів мелатоніну при експериментальній виразці шлунка відбувається у щурів-самців віком 9 та 20 міс., що відповідає віку людини 29–30 та 55–56 років.

Determination of the panel of reference genes for quantitative real-time PCR in fetal and adult rat intestines

In quantitative real-time PCR (qRT-PCR) detection, the stability of reference genes varies with different organs, tissue locations, sex and developmental stages. This study aimed to screen out and determine the optimal panel of reference genes of the intestine in pre- and post-natal rats of different sex. We used qRT-PCR to detect the mRNA expression of six commonly used reference genes (ACTB, GAPDH, HPRT1, B2M, RPLPO and SDHA) in rat intestines at gestational day 21 (GD21) and postnatal week 12 (PW12). Using GeNorm, BestKeeper and NormFinder software comprehensively analyzed the stability of candidate reference genes and screened out stable reference genes. Further, we used the pathological model of prenatal dexamethasone exposure (PDE) to verify the stability of the selected panel of reference genes. Based on the results of the software analysis, the optimal panel of reference genes in the fetal rat intestine was SDHA + ACTB, and the adult rat small intestine and colon were ACTB + HPRT1 and RPLP0 + GAPDH, respectively. There was no significant sex difference in the above results. Besides, in the PDE model, the results were consistent with those under physiological conditions. Therefore, the stability of intestinal reference genes in fetal rats and adult rats was different, and the intestinal reference genes of adult rats were intestinal segments-specific. The selected panel of reference genes was still stable under pathological conditions. This study determined the optimal panel of reference genes of pre- and post-natal rat intestines and provided reliable reference genes for the qRT-PCR analysis of rat intestines.

Analysis of the effect of vitamin D supplementation and sex on Vdr, Cyp2r1 and Cyp27b1 gene expression in Wistar rats' tissues

Vitamin D supplementation is widely recommended for animals and humans. However, its effects on extra-skeletal disorders have not been well proven. Our research aimed to analyse the effect of supplementation with standard and increased doses of vitamin D on the health status, biochemical and haematological parameters of blood as well as on the level of expression of genes metabolising vitamin D and the Vdr gene in the kidney, liver, fat and brain of rats of different sexes. 36 Wistars rats (18 males and 18 females) divided into three supplementation groups (I–O vitamin D, II- 1000 U / kg of vitamin D, III - 5000 U / Kg of vitamin D) were analysed. Vitamin D supplementation had little effect on growth traits and biochemical blood indices; slight decrease in a heart size was observed in females supplemented with high doses of vitamin D (p = 0.0075), moreover male rats tended to have increased level of triglyceride (TG) (p = 0.0516)). In our study we observed that vitamin D supplementation did not change the expression of Vdr gene in any of analysed tissue. However, we noticed evident downregulation of Cyp27b1 gene by vitamin D supplementation in the liver and kidney in a dose-dependent manner. Additionally, we observed that in the female's liver, Vdr and Cyp2r1 were upregulated, in the female's kidney Vdr was upregulated while Cyp27b1 was downregulated compared to males. Moreover, in the female's brain and fat Cyp27b1 and Cyp2r1 tended to be upregulated compared to males. Our results confirm that Vdr and vitamin D metabolising genes are regulated by sex in the kidney and several extra-renal tissues.

Оригінальний спосіб вилучення та фіксації гіпофіза статевозрілих щурів для приготування якісних постійних гістологічних препаратів

The issue of high-quality creating histological preparations is an urgent issue of histology and pathological anatomy, experimental medicine and biology. The pituitary gland belongs to the smallest in mass and size of the endocrine glands in both humans and animals, it is an endocrine gland and occupies one of the central places in the endocrine regulation of the body's vital activity. The study of the features of the removal of the pituitary gland from Turkish saddle of the sphenoid bone of the skull of rats remains an important aspect of modern morphology. The purpose of the work was to develop an original technique for improving the first (removal) and second (material fixation) stages of creating histological preparations of the rat pituitary gland for morphological, morphometric, and immunohistochemical medico-biological experimental studies. Material and methods. The development of the methodology was carried out on 200 white sexually mature rats of different sex weighing 250-300 g at the age of 7-8 months in accordance with the National and European bioethical standards. Results and discussion. Modification of the technique of extracting the pituitary gland of rats includes the introduction of the animal into thiopental anesthesia, decapitation, separation of the skin and muscular integument of the head, resection of the occipital bone of the skull, exposure and removal of the brain, identification of the pituitary gland, followed by removal of the pituitary gland with a single complex (block) together with the pituitary fossa Turkish saddle and fragments of the sphenoid bone adjacent to it. The gland was fixed with a reduced concentration of a 5% solution of buffered neutral formalin. After 15-18 hours from the beginning of fixation, the complex was temporarily removed from the fixator, and the pituitary gland was removed from the pituitary fossa of Turkish saddle using eye scalpel and eye forceps. The organ had a well-fixed and compacted capsule, which prevented unnecessary trauma and fragmentation of the organ during removal. The removed pituitary gland was again immersed in a 5% solution of neutral buffered formalin for 2-3 hours. After the end of the fixation period, the pituitary gland had a well-fixed structure and was subject to the following standard stages of making permanent histological specimens

Assessment of low intensivities γ-irradiation chronic influence on the state of thiol-disulphide exchange in the small intestine of rats

Today considerable attention is paid to the effects of ionizing radiation.chronic exposure in low doses and intensivity to humans and other bio-objects. The changes in the structural characteristics of the genome, nuclear, microsomal, mitochondrial, plasma membranes, cell proliferation, and the processes underlying radioresistance / radiosensitivity caused by irradiation have been experimentally studied. prolonged exposure to ionizing rays in small doses gradually causes a decrease in the endogenous reserve of thiol-dependent systems, and their complete depletion, which negatively affects the body's resistance to adverse environmental factors. There is a possibility of disturbances in the synthesis of thiol disulfide high molecular weight components. The objective: to study the state of thiol disulfide, glutathione redox system and acetylcholinesterase activity in the small intestine of rats of different sexes and ages under physiological conditions and under conditions of prolonged γ-irradiation in a total dose of 0.75 and 1.0 Gy. Results. It has been established that in a small bowel of intact mature rats after prolonged total γ-irradiation with a dose of 1.0 Gy, there were quite significant changes in the content of thiol compounds in the tissues of the small intestine. It was found that the content of SH-groups of protein origin in the tissues of the small intestine decreased relative to the age of control group animals by 28.8% and at the same time was lower than the value of males of the previous stage by 32.8%. The number of disulfide groups of protein origin in the small intestine of males three months after irradiation at a total dose of 1.0 Gy, relative to the same age control group animals, was 85.6% and at the same time was lower than the previous stage by 31.8%. Conclusions: 1.Under physiological conditions there are clear gender and age differences in the functional state of thiol-disulfide, glutathione redox system and acetylcholinesterase activity.Prolonged total γ-irradiation in the total dose of 0.75 and 1.0 Gy causes quite stable and profound changes in the functional state of the systems under study.The dependence of the detected changes on the time elapsed after radiation damage, the dose of γ-irradiation and the sex of the animals is clearly monitored.4. Females have been shown to be more radioresistant than males.

Impact of hypoxic-ischemic injury on brain development in neonatal rats of different sexes

Objective: To investigate the impact of hypoxic-ischemic brain injury (HIBI) on brain development in neonatal rats of different sexes. Methods: From January 1 to December 31, 2018, 60 7-day-old SD rats were randomly divided into HIBI-F group (20 rats), HIBI-M group (20 rats), and control group (20 rats, 10 females and 10 males). The animal model of HIBI was established with Rice-Vannucci method, with the rats' left common carotid artery double-ligated and severed. The rats were then placed in an incubator and exposed to a hypoxic gas mixture (8% O(2), 92% N(2)) for 90 minutes. No intervention was given to the control group. Two weeks after HIBI, the motor development was evaluated by footprint analysis, the residual brain volume was measured by brain magnetic resonance imaging (MRI), and the damage of synaptic ultra structure was analyzed by transmission electron microscope. One-way ANOVA or χ(2) test was used for inter-group statistical analysis, and paired sample t test was used to compare the bilateral step length and toe distance of rats in the same group. Results: The mortality rate of HIBI-F was significantly higher than that of HIBI-M (20%(4/20) vs. 10%(2/20), χ(2)=40.000, P=0.001). The right step length and toe distance in HIBI-M group and HIBI-F group were significantly shorter than those in control group ((7.5±0.3) cm and (7.9±0.5) cm vs. (8.2±0.5) cm, F=9.605, P<0.01, (0.9±0.1) cm and (1.0±0.0) cm vs. (1.1±0.1) cm, F=71.437, P<0.01). Besides, according to above data, the right step length and toe distance in HIBI-M group were significantly shorter than those in the HIBI-F group (both P<0.01). Furthermore, the right step length was significantly shorter than the left step length ((8.3±0.4) and (8.3±0.5) cm, t=5.289 and 10.580, P=0.001 and 0.010, respectively) and toe distance ((1.1±0.1) and (1.1±0.1) cm, t=7.953 and 6.435, respectively, both P<0.01) in both HIBI-M group and HIBI-F group. Similarly, the synaptic gap of the left precentral gyrus neurons was longer in HIBI-M group and HIBI-F group than that in control group ((23.4±1.3) and (19.7±1.6) nm vs. (18.9±0.6) nm, F=71.719, P<0.01), and also longer in HIBI-M group than that in HIBI-F group (t=7.645, P<0.01). Likewise, the residual brain volume in HIBI-M group and HIBI-F group was significantly less than that in control group ((67±4)% and (75±5)% vs. 100%, F=406.122, P<0.01), and the residual brain volume in HIBI-M group was significantly less than that in HIBI-F group (t=-5.281, P<0.01). Conclusions: Male neonatal rats are more vulnerable to HIBI and have severer subsequent brain injury and hemiplegia. Different treatment strategies for HIBI patients of different sexes should be developed.

Morphology of GFAP-Positive Cells in Male and Female Rats’ Cerebral Cortex during the Cerebral Hypoxia Development according to the Stress Tolerance Level

Correlation between individual typological features like sex-related characteristics and low initial level of stress resistance and unfavorable prognosis of ischemic brain damage is shown. At the same time, the astrocytes’ participation in neuroplasticity in this disease represents the purpose of the study. The goal was to study the cerebral cortex astrocytes’ morphometric characteristics during the cerebral hypoxia in rats of different sexes with different stress tolerance levels. We performed the study with 72 Wistar rats. According to the Open Field test results all the animals were divided into two subgroups: with high and low level of stress tolerance. Both carotid arteries of the experimental group animals (48 animals) were bandaged. Animals were removed from the experiment at 21, 60 and 90 days after surgery. Glial fibrillary acidic protein (GFAP), a marker of mature astrocytes, was detected on histological sections of the central brain gyrus using primary polyclonal rabbit antibodies. Progressive decrease of the astrocytes’ numerical density and the number of first order processes were obtained during the study. It was less pronounced in animals with high stress tolerance and females. Increase of the processes’ distribution area was reliably detected. Area decreased after 90th day of the experiment. It is concluded that the astrocytes’ alteration develops earlier in animals with high stress tolerance and males, later in females (60 days) and animals with low stress tolerance (90 days).

Моделювання артеріальної гіпертензії шляхом тривалого сольового навантаження. Моніторинг функціонування серцево-судинної системи та динаміки інтегральних показників життєдіяльності в щурів (частина II)

Запропоновано нову модель артеріальної гіпертензії (АГ), індуковану тривалим сольовим навантаженням. Розробка такої моделі базується на ролі натрію хлориду у функціонуванні життєво важливих органів і систем, у генезі АГ та її судинних порушень. Недостатня вивченість механізмів розвитку сольової АГ, фазності та тривалості патологічного стану за умов продовження сольового навантаження на тривалий час (до декількох місяців), особливостей дії різних лікарських засобів на тлі підвищеного споживання солі, стану серцево-судинної системи та інтегральних показників життєдіяльності зумовили мету дослідження. Мета дослідження – вивчити стан серцево-судинної системи та динаміку інтегральних показників життєдіяльності в білих щурів за формування АГ шляхом тривалого сольового навантаження. Формування нової моделі АГ забезпечувалося сольовим навантаженням щурів упродовж 81 доби за умов заміни води на 1 % розчин натрію хлориду з вільним доступом тварин до пиття. За проведення динамічних досліджень встановлено, що модель АГ характеризується суттєвим підвищенням артеріального тиску на 10–18 % у самиць і на 14–36 % у самців, про що свідчать зміни зазначеного показника в різні терміни від початку до 81 доби сольового навантаження. Значне зростання артеріального тиску спостерігалося в 54,5–66,6 % тварин упродовж 60 діб від початку сольового навантаження, водночас кількість тварин з підвищеним артеріальним тиском знижувалася до 23,6 % через 81 добу від початку сольового навантаження. Продовження сольового навантаження понад 21 добу характеризувалося розвитком брадикардії. Збільшення терміну сольового навантаження в щурів не призводило до суттєвої зміни інтегральних показників життєдіяльності різних органів і систем, патологічної зміни маси тіла тварин і коефіцієнтів маси внутрішніх органів, у тому числі тимуса. За формування АГ на 18–30 % знижувалася больова чутливість у щурів і спостерігався набряк кінцівок (суглобів і м’яких тканин стоп), що зростав з тривалістю сольового навантаження й перевищував значення в інтактних тварин понад 21 % через 81 добу від початку формування моделі АГ. Запропонована модель АГ відрізняється простотою формування, економічністю, досягненням відповідного ефекту в значної кількості щурів різної статі, можливістю відбору тварин з підвищеним артеріальним тиском на будь-якому етапі формування патологічного процесу, можливістю їхнього утримання за звичайних лабораторних умов, відсутністю загибелі тварин. Формування моделі АГ шляхом тривалого сольового навантаження не потребує спеціальної підготовки фахівців. Модель АГ за тривалого сольового навантаження пропонується для дослідження специфічної фармакологічної ефективності (гіпотензивної дії) і безпечності новосинтезованих сполук і відомих ліків за умов їхнього тривалого застосування.