Outbred Rats Research Articles

Genome-wide association study reveals multiple loci for nociception and opioid consumption behaviors associated with heroin vulnerability in outbred rats.

The increased prevalence of opioid use disorder (OUD) makes it imperative to disentangle the biological mechanisms contributing to individual differences in OUD vulnerability. OUD shows strong heritability, however genetic variants contributing toward vulnerability remain poorly defined. We performed a genome-wide association study using over 850 male and female heterogeneous stock (HS) rats to identify genes underlying behaviors associated with OUD such as nociception, as well as heroin-taking, extinction and seeking behaviors. By using an animal model of OUD, we were able to identify genetic variants associated with distinct OUD behaviors while maintaining a uniform environment, an experimental design not easily achieved in humans. Furthermore, we used a novel non-linear network-based clustering approach to characterize rats based on OUD vulnerability to assess genetic variants associated with OUD susceptibility. Our findings confirm the heritability of several OUD-like behaviors, including OUD susceptibility. Additionally, several genetic variants associated with nociceptive threshold prior to heroin experience, heroin consumption, escalation of intake, and motivation to obtain heroin were identified. Tom1, a microglial component, was implicated for nociception. Several genes involved in dopaminergic signaling, neuroplasticity and substance use disorders, including Brwd1, Pcp4, Phb1l2 and Mmp15 were implicated for the heroin traits. Additionally, an OUD vulnerable phenotype was associated with genetic variants for consumption and break point, suggesting a specific genetic contribution for OUD-like traits contributing to vulnerability. Together, these findings identify novel genetic markers related to the susceptibility to OUD-relevant behaviors in HS rats.

Potential hepatoprotective properties of synthetic derivatives of thiourea — 2-aminobenzothiazole and IEM-2320

BACKGROUND: Toxic hepatitis is characterized by a significant severity of the course and by high mortality. So, search for effective means of correcting this condition seems to be relevant. It has previously been shown that some thiazolo[5,4-b]indole derivatives are capable to prevent experimental toxic liver damage in laboratory animals. In continuation of this direction, the study of the hepatoprotective properties of synthetic derivatives of thiourea 2-aminobenzothiazole and IEM-2320 was undertaken. AIM: To study the potential hepatoprotective properties of 2-aminobenzothiazole and IEM-2320 in acute carbon tetrachloride poisoning. MATERIALS AND METHODS: Experiments were carried out on 30 male white outbred rats (150–270 g). On a model of carbon tetrachloride poisoning (50% solution of CCl4 in vaseline oil, 0.2 ml/100 g of body weight), the potential hepatoprotective properties of 2-aminobenzothiazole (32 mg/kg) and IEM-2320 (20 mg/kg) were investigated. Ademethionine (Heptral, AbbVie, S.r.L, Italy) at a dose of 20 mg/kg was used as a comparison drug. The studied drugs were administered intraperitoneally 4 times: one hour before the introduction of CCl4, and then — for three subsequent days after the poisoning with CCl4. The results were compared with those of 2 control groups. Animals of the 1st control group were not exposed to CCl4, instead of the studied drugs, they were injected with an equivalent volume of saline solution (0.2 ml/100 g of body weight). Animals of the 2nd control group did not receive any treatment after the CCl4 poisoning. Blood was taken on the seventh day of the experiment. The total contents of protein, glucose, and total cholesterol in blood serum were determined, and the activities of alanine aminotransferase and aspartate aminotransferase were evaluated. RESULTS: Under the CCl4 poisoning, the administration of 2-aminobenzothiazole led to a significant decrease in the concentrations of glucose, total protein, total cholesterol and alanine aminotransferase activity. When IEM-2320 was administered under the condition of poisoning, a decrease in the concentrations of total protein, glucose, urea, total cholesterol, and the alanine aminotransferase activity was observed. CONCLUSIONS: A significant decrease in the biochemical parameters of blood serum after administration of 2-aminobenzothiazole and IEM-2320 under the condition of CCl4 poisoning demonstrates thir potential hepatoprotective properties under acute hepatotropic poisonings.

Comparative assessment of the nature of the combined action of insecticides: different methodical approaches

Introduction. Pesticide mixtures containing insecticide methomyl are commonly used in agriculture. However, the interaction of their active ingredients in a mixture has been insufficiently studied. The purpose of the study was to evaluate the nature of the combined action of a mixture of insecticides methomyl (carbamate) and bifenthrin (pyrethroid) using various methods: a classical model (orthogonal planning of the experiment using nonlinear variables); a generalized linear regression model for the binomial distribution (probit regression); and an isobologram. The study was conducted at the Federal Scientific Center of Hygiene named after F.F. Erisman of the Federal Service for Supervision in Protection of the Rights of Consumer and Man Wellbeing, according to the protocol approved by the local bioethical commission. Materials and methods. Ninety male outbred rats were administered 9 combined doses of the insecticides (combinations of LD16, LD33 and LD50 for the individual compounds, as devised from a preliminary study). Results. Impaired coordination, tremor of the limbs and head, turning into convulsions, rapid (shallow) breathing were observed in all groups. The data on mortality as used to construct 2 mathematical models, as well as to construct an isobologram. Limitations. The study was limited to studying the indicators of acute oral toxicity, without taking into account the possible repeated exposure. Conclusion. The models showed that the additive effect for the combination of methomyl and bifenthrin was only observed for combinations when the individual dose of bifenthrin was equal to or greater than 45 mg/kg b.w. (LD33) and the dose of methomyl was less than 30 mg/kg b.w., as all animals receiving a dose of 30 mg/kg b.w. of methomyl (LD50) in the mixture died. Therefore, the dose of methomyl dictated the toxic effect of the mixture, which should be accounted for in hygienic regulation of methomyl-containing formulations.

LEVELS OF HEAT SHOCK PROTEIN HSP70 IN NEURONS OF PARIETAL CORTEX AND HIPPOCAMPUS IN RATS WITH VARIOUS STAGES OF CEREBRAL ISCHEMIA

The paper examines the issue of increasing the body’s resistance to oxygen deficiency and energy deficit under cerebral ischemia. Adaptation to these changes is represented by an increased number of heat shock proteins in brain neurons. Their expression increases with a decrease of oxygen level in the blood. The aim of the paper is to evaluate HSP70 level in the brain of rats with various stages of cerebral ischemia. Materials and Methods. The study was conducted on 27 white outbred male rats weighing 267±16 g. The authors used such models as partial cerebral ischemia, step-by-step 90 % blood flow shutdown, one-time 90 % blood flow shutdown, and complete cerebral ischemia. Results. In the 1st subgroup of step-by-step 90 % blood flow shutdown (7 days between dressings) there was an increase in the HSP70 level by 25 % in the parietal cortex (p<0.05) compared with the control. However, its concentration in the hippocampus did not change (p>0.05). In the 2nd and 3rd subgroups of step-by-step 90 % blood flow shutdown (3 days and 1 day between dressings), the HSP70 level did not change in any of the studied areas (p>0.05) compared with the control. Compared with the 1st subgroup, in the 2nd subgroup HSP70 level in the parietal cortex was lower by 26 % (p<0.05) and in the hippocampus by 20 % (p<0.05), in the 3rd subgroup it was lower by 30 % (p<0.05) and by 23 % (p<0.05), respectively. No differences in HSP70 levels were found between the 2nd and 3rd subgroups (p>0.05). In the group of one-time 90 % blood flow shutdown, the HSP70 level decreased by 29 % in the parietal cortex (p<0.05) and by 18 % in the hippocampus (p<0.05) compared with the control. In group of one-time 90 % blood flow shutdown, the HSP70 level did not differ from those in the 2nd and 3rd subgroups of step-by-step 90 % blood flow shutdown in the hippocampus. In the parietal cortex, the HSP70 level in the 2nd subgroup was 28 % higher (p<0.05), and in the 3rd subgroup by 23 % higher (p<0.05) compared with the group of one-time 90 % blood flow shutdown. In total cerebral ischemia, the most significant decrease in HSP70 level was observed compared to the control: by 35 % in the parietal cortex (p<0.05) and by 36 % in the hippocampus (p<0.05). Conclusion. Thus, in the 1st subgroup with the maximum interval between dressings, the HSP70 level increased, indicating the activation of compensation mechanisms during hypoxia by protecting proteins from premature proteolytic breakdown and promoting the correct polypeptide folding into a tertiary structure.

Structural changes in the organs of the lymphoid system in terms of induced carcinogenesis

Colorectal cancer is the third most common cancer in the world. Despite recent therapeutic advances, it causes more than 500,000 deaths each year. The immune system plays a crucial role in protecting the body from cancer. However, cancer cells are able to evade immune detection and destruction. For example, they can downregulate antigen expression, produce immunosuppressive molecules, or recruit immune cells that perform regulatory or inhibitory functions. Understanding the complex interactions between the immune system and carcinogenesis is crucial for developing effective cancer treatments. The study aimed to determine the morphological changes in the thymus, spleen, and lymph nodes under N,N-dimethylhydrazine-induced carcinogenesis. The study was performed on 77 male outbred albino rats weighing 190-230 g, kept in standard vivarium conditions. Colon adenocarcinoma was modeled by administration of N,N-dimethylhydrazine hydrochloride for 30 weeks. To study the peculiarities of morphological and functional changes in lymphoid organs in the dynamics of colon tumor lesions, animals were withdrawn from the experiment every 30 days. Paraffin sections of the thymus, spleen, and lymph nodes 5-6 μm thick were made on a rotary microtome and stained with hematoxylin and eosin. The experimental investigation unveiled the character and extent of histological alterations within the lymphoid system organs under conditions of N,N-dimethylhydrazine-induced colon adenocarcinomatosis. As the experiment progressed, there was a noticeable escalation in the severity of detrimental and degenerative modifications observed in the thymus, spleen, and lymph nodes. These modifications were evident in the disruption of blood circulation within the examined organs, leading to vascular wall impairment and hemorrhaging, the disarray of morphofunctional elements and the development of fibrosis. Given the significant role played by the thymus, spleen, and lymph nodes in regulating carcinogenesis and maintaining immune balance, it is extremely important to delve into understanding the changes in their structure and function. Obtained results indicate that carcinogenesis is accompanied by pronounced morphological changes in the structural components of the lymphoid system organs, the degree of which increases in direct proportion to the duration of exposure to the oncogenic factor.

Acute toxicity of antiparasitic selamectin-based drug

The purpose of the research is to evaluate some toxicological parameters of antiparasitic selamectin-based drug.Materials and methods. The study drug is a solution for external use, 1 mL of which contains the active component selamectin (120 mg), as well as additives. The experiments used a total of 66 white outbred male rats, 42 white outbred male mice and 3 guinea pigs. The parameters of acute oral toxicity (in mice and rats), acute dermal toxicity (in rats), and dermal and mucous membrane irritation (in rats and guinea pigs) of antiparasitic selamectin-based drug were evaluated. LD50 was calculated and the irritation of the drug was evaluated using established procedures in toxicology.Results and discussion. The maximum tolerated dose of the selamectin-based drug was 2550 mg/kg in the mice and 4250 mg/kg in the rats. The absolutely lethal dose for the mice and the rats was 6800 and 8500 mg/kg, respectively. It was established that the drug belonged to hazard class 3 (moderately hazardous substances) when administered intragastrically to the animals: LD50 for the mice was 4816.7 mg/kg, and LD50 for the rats was 6091.7 mg/kg. In determining acute dermal toxicity in the rats, the drug was classified as hazard class 4 (low-hazardous substances): LD50 more than 8500 mg/kg. The drug irritant effect on the skin of the rats at doses of 4250, 6375 and 8500 mg/kg was not established. The drug had a mild effect on the mucous membrane of the eyes of the guinea pigs with its recovery to normal within 24 hours.

Доклиническая оценка безопасности нового лекарственного препарата для собак и кошек Supramil® эмульсия

This article presents the results of a toxicological evaluation of a new drug for veterinary use, Supramil® emulsion based on R-praziquantel and milbemycin oxime. The drug is intended for the treatment of intestinal nematodes and cestodes, mixed infestations in cats and dogs, as well as for the prevention of dirofilariasis. A single intragastric administration of the drug in doses of a toxic level for rats and mice did not cause toxicosis or death in laboratory animals, on the basis of which the average lethal dose (LD50) for the drug Supramil® emulsion could not be determined. As a result of the assessment of subchronic oral toxicity, it was established that the tested doses of the drug when administered daily to white outbred rats for 14 days are ineffective. An assessment of the ability of the drug, when introduced into the body, to cause a state of hypersensitivity did not reveal an allergenic effect. Thus, the results of this study allow us to conclude that the Supramil® emulsion does not have toxic or allergenic properties and is well tolerated by laboratory animals.

Calix[4]arene С-956 as a selective inhibitor of Ca2+-pump of the plasma membrane and a modulator of the contractile function in the myometrium

Background. At present, creating and testing pharmacological instruments for selective inhibition of Са2+-pump of the plasma membrane, which would become the foundation for medical preparations, for instance, for the treatment of the impaired excitability of the cardiac and smooth muscles, remains critically significant. We have demon­strated in our previous experiments that calix[4]arene С-956 is effective in inhibi­ting Са2+, Mg2+-ATPase activity of the plasma membrane of myometrium cells. The aim of this study was to investigate the regularities and mechanisms of the impact of calix[4]arene С-956 on Са2+-transporting activity of Са2+, Mg2+-ATPase of the plasma membrane (PM) and the contractile function of rat myometrium. Materials and Methods. The experiments were conducted using outbred white non-pregnant rats. Ca2+-transporting activity of myocytes PM preparations loaded with Ca2+-sensitive fluorescent probe fluo-4 AM was investigated. The registration of the contractile activity in the preparations of longitudinal smooth muscles of uterine horns with preserved endothelium was done in the isometric mode. Results. It was determined that calix[4]arene C-956 causes blocking of the transport function of the calcium pump of preparations of plasma membranes of uterine myocytes. The C-956 compound causes an increase in the amplitude of spontaneous contractions and a change in their mechanokinetic parameters during a short-term effect on multicellular preparations of rat myometrium. Calix[4]arene C-956 also significantly affects the contractions caused by high-potassium depolarization of the PM and oxytocin, increa­sing their amplitude and decreasing the rate of relaxation. Blocking the synthesis of nitric oxide significantly enhances the effects of C-956 on spontaneous and high-potassium- and oxytocin-induced contractions of the myometrium. Conclusions. The results of our research indicate that the main target of the action of calix[4]arene C-956 on myocytes is the calcium pump of the PM. With the preliminary inhibition of nitric oxide synthases followed by the use of C-956, we were able to fully demonstrate the contribution of the calcium pump of the PM to the regulation of uterine contractions.

S100b protein as a biological marker of nerve tissue damage in laboratory animals in preclinical studies

Background. For preclinical studies of drugs a relevant task is the selection of specific biochemical markers reflecting damage to the central nervous system, both in toxicological and pharmacological experiments. One of such markers may be protein S100b, the level of which will make it possible to assess the damage of the central nervous system of various genesis. Objective. The aim of the study was to assess changes in the level of S100b protein in the blood and in brain homogenates in brain tissue injuries of various genesis. Design and methods. The study was conducted on males of outbred rats and mice. A total of 62 animals were used: 47 rats and 15 mice. To determine the concentration of S100b protein, ELISA kits Rat S100b/S100 beta Elisa kit (Sandwich Elisa) were used) for rats and Mouse S100b/S100 beta Elisa kit (Sandwich Elisa) for mice. Statistical analysis was performed using licensed GraphPad Prism 9 software. Results: Changes of protein S100B was explored on models of alcohol neuropathy, bilateral and focal cerebral ischemia, traumatic brain injury. Forming of all pa[1]thologies led to increasing of protein S100B both in blood plasma and in brain tissues in case of traumatic brain injury. For alcohol neuropathy, focal and cerebral ischemia and traumatic brain injury changings of this marker level reached statistic meaning. Conclusion. Increased concentration of S100b is a sign of neuronal damage as a result of ischemic, traumatic and toxic factors, as well as in hypoclycemic conditions. Thus, protein S100b can be used in preclinical studies as a marker of brain damage, responding to damage of various genesis in studies of pharmacodynamics and pharmacological safety of drugs.

Beta-Blockers of Different Generations: Features of Influence on the Disturbances of Myocardial Energy Metabolism in Doxorubicin-Induced Chronic Heart Failure in Rats.

Beta-blockers are first-line drugs in the treatment of chronic heart failure (CHF). However, there is no consensus on the specific effects of the beta-blockers of the I-III generation on energy metabolism in CHF. The aim of this study is to conduct a study of beta-blockers of different generations on myocardial energy metabolism in experimental CHF. CHF was modeled in white outbred rats by administering doxorubicin. The study drugs were administered intragastrically-new drug Hypertril (1-(β-phenylethyl)-4-amino-1,2,4-triazolium bromide)-3.5 mg/kg, Metoprolol-15 mg/kg, Nebivolol -10 mg/kg, Carvedilol 50 mg/kg, and Bisoprolol, 10 mg/kg. In the myocardium, the main indices of energy metabolism were determined-ATP, ADP, AMP, malate, lactate, pyruvate, succinate dehydrogenase (SDH) activity, and NAD-dependent malate dehydrogenase (NAD-MDH) activity. Traditional second-generation beta-blockers (Metoprolol and Bisoprolol) did not affect the studied indices of energy metabolism, and third-generation beta-blockers with additional properties-Carvedilol and, especially, Nebivalol and Hypertril-improved myocardial energy metabolism. The obtained results will help to expand our understanding of the effect of beta-blockers of various generations used to treat cardiovascular diseases on energy metabolism, and are also an experimental justification for the practical choice of these drugs in the complex therapy of CHF.

A brain death model with slow induction for experimental studies of organ donation

Aim. To test in experiment a pathogenetically adequate model of brain death due to increased intracranial pressure with gradual induction, allowing the evaluation of the changes occurring in the organs of a potential donor.Materials and methods. 6–8 months old outbred male rats of the experimental group (n = 18) and the control group (n = 8) were anesthetized, the left common carotid artery was catheterized to record systolic, diastolic blood pressure (BP) and heart rate (HR), the mean BP (MBP) was calculated. After transfer to artifi cial ventilation, brain death was simulated in the experimental group using the developed method.Results. All animals in the experimental group suffered brain death 30 minutes from the start of the experiment;10 rats (56%) died within 3 hours due to progression of circulatory failure. Initially, in anesthetized animals, MBP was 101 (90; 105) mm Hg, HR 310 (297; 315) beats/min. After 5 minutes from the start of brain death induction, MBP increased to 147 (140; 150) mm Hg (p = 0.01), HR to 396 (384; 406) beats/min (p = 0.03). Further, within 20 minutes there was a decrease in MBP to 94 (90; 100) mm Hg and HR to 290 beats/min. During the observation period from 26 to 90 minutes, there was a stabilization of MBP at the level of 87–92 mm Hg, there was a tendency to bradycardia with HR from 263 to 274 beats/min (p = 0.01). Then after 120–150 minutes from the beginning of brain death induction, MBP continued to decrease to 75–80 mmHg (p = 0,03), HR to 256–264 beats/min (p = 0,01). At the end of the experiment, despite volemic support, MBP decreased to 64 (61; 67) mm Hg (p = 0.02), bradycardia worsened with HR to 250 (248; 260) beats/min (p = 0.01), indicating the hemodynamic decompensation.Conclusion. The results of experimental testing of an animal brain death model on outbred rats showed that this model is pathogenetically adequate and useful to assess the condition of potential donor organs within 3 hours after the induction of brain death.

Neurotoxic Methamphetamine Doses Alter CDCel-1 Levels and Its Interaction with Vesicular Monoamine Transporter-2 in Rat Striatum.

In recent years, methamphetamine METH misuse in the US has been rapidly increasing and there is no FDA-approved pharmacotherapy for METH use disorder (MUD). In addition to being dependent on the drug, people with MUD develop a variety of neurological problems related to the toxicity of this drug. A variety of molecular mechanisms underlying METH neurotoxicity has been identified, including dysfunction of the neuroprotective protein parkin. However, it is not known whether parkin loss of function within striatal dopaminergic (DAergic) terminals translates into a decrease in DA storage capacity. This study examined the relationship between parkin, its substrate cell division cycle related-1 (CDCrel-1), and vesicular monoamine transporter-2 (VMAT2) in METH neurotoxicity in male Sprague Dawley rats. To also assess individual differences in response to METH's neurotoxic effects, a large group of rats was treated with binge METH or saline and sacrificed 1h or 24h later. This study is the first to show that binge METH alters the levels and subcellular localization of CDCrel-1 and that CDCrel-1 interacts with VMAT2 and increases its levels at the plasma membrane. Furthermore, we found wide individual differences in the responses of measured indices to METH. Proteomic analysis of VMAT-2-associated proteins revealed upregulation of several proteins involved in the exocytosis/endocytosis cycle. The results suggest that at 1h after METH binge, DAergic neurons are engaged in counteracting METH-induced toxic effects, including oxidative stress- and hyperthermia-induced inhibition of synaptic vesicle cycling, with the responses varying between individual rats. Studying CDCrel-1, VMAT2, and other proteins in large groups of outbred rats can help define individual genetic and molecular differences in responses to METH neurotoxicity which, in turn, will aid treating humans suffering from METH use disorder and its neurological consequences.

Neuropeptide Y is involved in the regulation of the frequency and strength of rat atrium spontaneous contraction

BACKGROUND: The relevance of the problem increases due to the established cardioprotective effect of neuropeptide Y in pathological conditions such as hypertension, heart failure, and its possible therapeutic use in cardiovascular diseases. AIM: Study of the effect of neuropeptide Y on the frequency of spontaneous activity and amplitude-time parameters of the myocardium contraction of the rats’ right atrium during different periods of postnatal ontogenesis. MATERIAL AND METHODS: The experiments used 73 white outbred rats of 7 days (n=23), 21 days (n=25) and 100 days (n=25) of age. Using the classical strain-gauge method, the parameters of isometric contraction of isolated rat atrial myocardium were determined with the addition of a non-selective Y-receptor agonist. The isometric contraction curve was processed using the Chart 8.0 program. Statistical processing of the results was performed in MS Excel and IBM SPSS Statistics 2020. The significance of the differences was calculated using the Student’s t test. Data were presented as mean ± error of mean (M±m); n was the number of atrial myocardium preparations used. Changes were considered statistically significant at p 0.05. RESULTS: Neuropeptide Y at a concentration of 10–7 M reduces the frequency of spontaneous activity of the right atrium strips of rats with a preserved sinus node in 7, 21 and 100-day-old animals by 8.1%, 15% (p=0.038) and 7.9% (p=0.046) respectively in comparison with the control value. The amplitude of isometric contraction of the atrial myocardium in 7-day-old animals decreases by 12.4% (p=0.041), the duration of contraction decreases in 21-day-old animals by 12% (p=0.040), and in 100-day-old animals does not change compared to control. CONCLUSION: Neuropeptide Y reduces the frequency of spontaneous activity, increases the contraction duration, reduces the isometric contraction amplitude of rat myocardial strips in early postnatal ontogenesis.

ANK-1, ANK-2, ITL-2 Polyphenols in a Dexamethasone-Induced Rat Model of Type 2 Diabetes Mellitus Treatment

Background: Diabetes mellitus (DM) is a prevalent endocrine disorder that significantly increases the risk of cardiovascular complications due to the dysfunction of the coagulation and anticoagulation systems, exacerbated by metabolic imbalances. Despite advancements in understanding DM's pathophysiology, the precise alterations in the hemostatic system remain inadequately explored, posing challenges in diagnosis and treatment. This study investigated the effects of polyphenolic compounds isolated from Hexagalloy-lglucose (ANK-1), Hepta galloyl-glucose (ANK-2), and Isatis tinctoria L. (ITL-2) on biochemical and coagulation parameters in a dexamethasone-induced type 2 diabetes mellitus (T2DM) model in rats. Methods: T2DM was induced in 25 aged white outbred rats by administering dexamethasone (0.150 mg/kg) twice daily, with a control group receiving saline. Biochemical parameters, including glucose, total protein, ALT, AST, cholesterol, and triglycerides, were measured using a semi-automatic analyzer. Coagulation parameters such as prothrombin time (PT), activated partial thromboplastin time (APTT), plasma recalcification time (RP), and fibrinogen levels were assessed using a single-channel coagulometer. Platelet aggregation was recorded using an aggregometer, and clot degradation was measured spectrophotometrically. Results: Dexamethasone administration induced significant hyperglycemia and hypercoagulation, evidenced by reduced PT, APTT, and RP, alongside increased fibrinogen levels. The administration of ITL-2 normalized all biochemical parameters, while ANK-1 and ANK-2 normalized glucose, cholesterol, and triglycerides but not ALT and AST levels. ANK-1, ANK-2, and ITL-2 demonstrated significant antithrombotic effects, with ITL-2 showing the highest efficacy, reducing clot mass and enhancing clot degradation. Conclusion: Polyphenolic compounds, particularly ITL-2, exhibit potential as therapeutic agents for managing coagulation abnormalities and hyperglycemia in T2DM. These findings highlight the importance of further research into plant-derived substances as safer and effective alternatives in diabetes management.

Characteristics of HIF-1Α and HSP70 MRNA Expression, Level, and Interleukins in Experimental Chronic Generalized Periodontitis.

Periodontal diseases are a rather complex problem of modern dentistry and do not have only medical but also social significance. The objective of this study is to weigh the effect of a mixture of Thiotriazoline and L-arginine (1:4) on the parameters of the system of endogenous cytoprotection of blood and periodontal illness in rats with experimental chronic generalized periodontitis and substantiate further study of this blend. The study aimed to evaluate the impact of a combination of Thiotriazoline and L-arginine (in a ratio of 1:4) on the parameters of the endogenous blood cytoprotection system and periodontium in rats with experimental chronic generalized periodontitis. A group of outbred rats weighing 190-220 g and sourced from the vivarium of the Institute of Pharmacology and Toxicology of the Academy of Medical Sciences of Ukraine were divided into four groups, each consisting of 10 animals. (1) Intact group, animals that were injected intragastrically with a solution of sodium chloride to chloride 0.9% for 30 days. (2) control, animals with experimental CGP who intragastrically sodium chloride solution 0.9% for 30 days. (3) animals with experimental CGP were injected intramuscularly with Thiotriazoline + L-arginine (1:4) in a dosage of 200 mg/kg (30 days). (4) animals with experimental CGP, for which daily intragastric reference drug Mexidol, in dosage 250 mg/kg (30 days). In this study, we utilized two substances: Thiotriazoline and L-arginine hydrochloride. The combination of Thiotriazoline and L-arginine (in a ratio of 1:4) was prepared at the Department of Pharmaceutical Chemistry of ZSMU. At the conclusion of the experiment, the rats were carefully removed from the study while under thiopental-sodium anesthesia, and administered at a dosage of 40 mg/kg. We have found that the administration of a combined preparation of Thiotriazoline with L-arginine to rats with CGP leads to a significant decrease in the blood concentration of pro-inflammatory cytokines IL-1b and TNF-a by 56.1% and 71%, respectively. The administration of Mexidol at a dosage of 250 mg/kg, as well as the combination of Thiotriazoline and Larginine in a ratio of 1:4 at a dosage of 200 mg/kg, resulted in a significant reduction in gingival pocket depth in animals with CGP. Specifically, the gingival pocket depth was reduced to 6 mm (p < 0.05) with Mexidol and further reduced to 4 mm (p < 0.05) with the combination of Thiotriazoline and L-arginine. Additionally, the animals exhibited minimal bleeding, swelling, and tooth mobility when treated with the combination of Thiotriazoline and L-arginine. The administration of a combination of Thiotriazoline and L-arginine (in a ratio of 1:4) at a dosage of 200 mg/kg to animals with CGP resulted in a noteworthy reduction in the blood concentration of pro-inflammatory cytokines IL-1b and TNF-a. Specifically, there was a significant decrease of 56.1% (p < 0.05) in IL-1b and 71% (p < 0.05) in TNF-a levels. The course administration of a combination of Thiotriazoline and L-arginine (1:4) (200 mg/kg) to animals with CGP led to an increased expression of HSP70 mRNA (p < 0.05) in the periodontium by 8.2 times and HIF-1a mRNA by 8.2 times. 2.8 times (p < 0.05) against the background of an increase in the blood concentration of HSP70 by 95% (p < 0.05). Also, in the periodontium of animals in this group, a decrease in the expression of c-Fos mRNA by 36.7% (p < 0.05) was found compared to the control group.

Greater inhibition of female rat binge alcohol intake by adrenergic receptor blockers using a novel Two-Shot rat binge drinking model

Binge drinking (BD) contributes strongly to the harms of alcohol use disorder. Most rodent models do not result in binge-level blood alcohol concentrations (BACs), and to better understand individual and sex differences in neurobiological mechanisms related to BD, the use of outbred rat strains would be valuable. Here, we developed a novel BD model where after 3+ months of intermittent access to 20% alcohol Wistar rats drank, twice a week, with two 5-min intake (what we called Two-shot) separated by a 10-min break. Our findings showed during Two-Shot that most animals reached ≥ 80 mg% BAC levels (when briefly food-restricted). However, when increasing alcohol concentrations from 20 to 30%, 40%, or 50%, rats titrated to similar intake levels, suggesting rapid sensing of alcohol effects even when front-loading. Two-Shot drinking was reduced in both sexes by naltrexone (1 mg/kg), validating intake suppression by a clinical therapeutic agent for human problem drinking. Further, both propranolol (β-adrenergic receptor antagonist) and prazosin (α1-adrenergic receptor antagonist) reduced female but not male BD at the lower dose. Thus, our results provide a novel model for BD in outbred rats and suggest that female binging is more sensitive to adrenergic modulation than males, perhaps providing a novel sex-related therapy.

Forensic characteristics of injuries from thermo-baric explosive device

Since the beginning of the Russian Federation's invasion of Ukraine in 2022, explosive trauma has become an extremely urgent problem, as the main source of bodily injury among both the military in the combat zone and the civilian population in cities has been the impact of explosive devices. The aim of the study is the examination of the forensic characteristics of damage to biological objects that were formed from thermal exposure and shock wave as a result of the explosion of a cumulative munition and in the conditions of an experimental explosion model. The objects of the study were the materials of two examinations on the death of Ukrainian soldiers who died in the war zone (archival "Conclusions of the medical examination" of the Kyiv City Clinical Bureau of Forensic Medical Examination in 2023). Under the conditions of the experiment, studies of pathomorphological changes in the liver and small intestine of 30 white outbred rats from the action of an artificially created air shock wave with an overpressure of 31.62±4.84 kPa were carried out. The injuries were examined macroscopically and using standard laboratory histological techniques. Microscopy of histological sections was performed using an Axio Imager 2 microscope (Zeiss, Germany) at magnifications of ×200 and ×400. Statistical processing of the obtained quantitative results was carried out using the STATISTICA 6.1 software product. Under the condition of the explosion of the ammunition with the cumulative effect of the rocket-propelled infantry flamethrower "Bumblebee" on sectional incisions of the skin and muscles of the thigh in the projection of areas of redness, a picture of a gelatinous consistency of bright red color was macroscopically determined due to abundant blood impregnation of muscles and subcutaneous fat and partial loss of muscle structure with the release of myoglobin. The bright red color of the skin of the thigh and pelvis without burning the hair may indicate the superficial thermal effect of the explosive device and the protection of the skin by clothing. Diffusely located numerous both paired and single abrasions and shallow wounds, small rounded, oblong, circular in shape, which are the result of fragments of a rocket-propelled grenade equipped with a fire mixture, were also determined. The effect of an air shock wave with an overpressure of 31.62±4.84 kPa on the liver parenchyma of rats was determined by focal hemorrhages with rupture of the terminal central vein of the hepatic lobule, edema of the parasinusoidal spaces, and sludges in the sinusoids. In the wall of the small intestine, acute hemodynamic disorders occurred in the form of vasodilation of arterial vessels, venular and capillary stasis. There was layering and swelling of the small intestine wall, rupture of veins, focal hemorrhage. Thus, the revealed characteristic pathomorphological signs of the destructive effect of overpressure as a result of a blast wave (barotrauma) are typical and common both in the areas of the human thigh and pelvis, and in biological objects of experimental animals. The obtained results are consistent with the pathomorphological manifestations of barotrauma in areas of the human body as a result of the action of an explosive device with a cumulative effect.

Greater inhibition of female rat binge alcohol intake by adrenergic receptor blockers using a novel Two-Shot rat binge drinking model.

Binge drinking (BD) contributes strongly to the harms of alcohol use disorder. Most rodent models do not result in binge-level blood alcohol concentrations (BACs), and to better understand individual and sex differences in neurobiological mechanisms related to BD, the use of outbred rat strains would be valuable. Here, we developed a novel BD model where after 3+ months of intermittent access to 20% alcohol Wistar rats drank, twice a week, with two 5-minute intake (what we called Two-shot) separated by a 10-minute break. Our findings showed during Two-Shot that most animals reached ≥ 80mg% BAC levels (when briefly food-restricted). However, when increasing alcohol concentrations from 20% to 30%, 40%, or 50%, rats titrated to similar intake levels, suggesting rapid sensing of alcohol effects even when front-loading. Two-Shot drinking was reduced in both sexes by naltrexone (1mg/kg), validating intake suppression by a clinical therapeutic agent. Further, both propranolol (β adrenergic receptor antagonist) and prazosin (α1 adrenergic receptor antagonist) reduced female but not male BD at the lower dose. Thus, our results provide a novel model for BD in outbred rats and suggest that female binging is more sensitive to adrenergic modulation than males, perhaps providing a novel sex-related therapy.

Study Of The Stress-Protective Effect Of Sodium 2-((4-amino-5-(thiophen-2-ylmethyl)-4H-1,2,4-triazol-3-yl)thio)acetate

The aim was to study the stress-protective effect of sodium 2-((4-amino-5-(thiophen-2-ylmethyl)-4H-1,2,4-triazol-3-yl)thio)acetate. The analysis of the effect of the sample on the behavior and psycho-emotional state of animals, physiological parameters, antioxidant-prooxidant system was studied. Studies of stress-protective properties were performed on white outbred rats. As a comparison drug was used a Mebicar (Adaptol®) (reference sample). One hour after the simulation of immobilization 6-hour stress, the animals were subjected to a series of tests: "Open Field", "Light and Dark Chamber", "Morris Water Labyrinth". Behavioral tests were performed according to generally accepted methods in simplified modifications. Serum and liver homogenate were used to determine the content of markers of the antioxidant-prooxidant system: quantitative content of diene conjugates (DC), thiobarbituric acid reactants (TBA reactants), as well as catalase and superoxide dismutase (SOD) activity. Based on complex behavioral tests data, Catalase, TBA reactants, DC, SOD data in the serum and in the liver homogenate it can be concluded the presence of stress-protective properties of sodium 2-((4-amino-5-(thiophen-2-ylmethyl)-4H-1,2,4-triazol-3-yl)thio)acetate in the model of acute immobilization stress.

Effect of proline-containing oligopeptides on peculiarities of operant conditioning of behavior in outbred rats

Effect of proline-containing oligopeptides on peculiarities of operant conditioning of behavior in outbred rats