Swimming Time Of Rats Research Articles

Effect of intramyocardial injection of allogeneic biomaterial on the exercise tolerance after destructive injury to the heart muscle (experimental study)

Introduction. The low regenerative potential of the heart prevents replacing dead cardiomyocytes with new cells. It has been shown that cell-free allogeneic biodegradable material (ABM) can increase the efficiency of reparative processes in myocardium and improve its structural and functional state. However, how the physical training capabilities change against this background has not been practically studied. Aim. To evaluate exercise tolerance in rats after the use of ABM. Material and methods. The work was performed on Wistar rats. Myocardial damage was caused by coronary occlusion (CO) and cryodestruction (CD) of the left ventricle apex of the heart. ABM was injected into the CO zone and along the perimeter of the myocardium affected area during CD. Animals with myocardial damage were included in control groups. Rats with myocardial damage and ABM injection constituted the experimental groups. Rats were taken into the experiment 45 days after ABM injection. The physical tolerance of rats was measured using the forced swimming test. Results. It has been shown that the swimming time of rats with СO by 62.5 % and with CD by 37.5 % (p<0.05) is less compared to similar indicators for these animals in the initial (intact) state, which indicates a significant decrease in their exercise tolerance in myocardial damage. Animals with CO or CD on the background of intramyocardial injection of ABM showed 33 % and 48 % longer swimming during the test, respectively. The increase in exercise tolerance of rats against the background of the ABM administration was accompanied by the improvement in the morphometric parameters of the heart. Conclusion. The effect of ABM intramyocardial injection on the endogenous mechanisms of cardiac muscle regeneration is effective and functionally significant.

The effect of peptide bioregulators on the resistance of rats to cold-stress factor

BACKGROUND: Biologically active regulatory peptides are the drugs of new type that act selectively on targets, with having no significant side effects.
 AIM: The aim of the study was to study the potential effect of peptide preparations Cortexin and Semax on the resistance of the rat organism to the cold stress factor in the model of cold stress maladaptation.
 MATERIALS AND METHODS: White outbred male rats were injected intraperitoneally twice daily with placebo (n = 30), Cortexin 5 mg/kg (n = 30) or Semax 0.3 mg/kg (n = 30). Three days after the start of the injection course, the cold-stress effect was simulated in the climate chamber (Feutron, Germany) by cooling the air to 5C at a relative humidity of 7580%.
 RESULTS: The use of RP significantly increased the duration of the rectal temperature plateau-period within 35C (moderate hypothermia): in animals of the Cortexin group from 10 days to 12 days, and in animals of the Semax group, from 10 to 14 days. Cortexin demonstrated moderate immunomodulatory properties, and Semax had a more pronounced immunomodulatory effect. Both preparations showed a stress-protective effect. The use of regulatory peptides provided to delay the decrease in the rat general motor activity and exploratory behavior which develops under the influence of a simulated cold-stress factor. A slower rate of decrease in the swimming time of rats under the influence of regulatory peptides was registrated.
 CONCLUSIONS: The meteoadaptogenic, stress-protective and nootropic effects of the regulatory peptides Cortexin and Semax were confirmed in rats on the model of cold-stress maladaptation.

Screening the effective components in treating dampness stagnancy due to spleen deficiency syndrome and elucidating the potential mechanism of Poria water extract.

Poria is an important medicine for inducing diuresis to drain dampness from the middle energizer. However, the specific effective components and the potential mechanism of Poria remain largely unknown. To identify the effective components and the mechanism of Poria water extract (PWE) to treat dampness stagnancy due to spleen deficiency syndrome (DSSD), a rat model of DSSD was established through weight-loaded forced swimming, intragastric ice-water stimulation, humid living environment, and alternate-day fasting for 21 days. After 14 days of treatment with PWE, the results indicated that PWE increased fecal moisture percentage, urine output, D-xylose level and weight; amylase, albumin, and total protein levels; and the swimming time of rats with DSSD to different extents. Eleven highly related components were screened out using the spectrum-effect relationship and LC-MS. Mechanistic studies revealed that PWE significantly increased the expression of serum motilin (MTL), gastrin (GAS), ADCY5/6, p-PKAα/β/γ cat, and phosphorylated cAMP-response element binding protein in the stomach, and AQP3 expression in the colon. Moreover, it decreased the levels of serum ADH, the expression of AQP3 and AQP4 in the stomach, AQP1 and AQP3 in the duodenum, and AQP4 in the colon. PWE induced diuresis to drain dampness in rats with DSSD. Eleven main effective components were identified in PWE. They exerted therapeutic effect by regulating the AC-cAMP-AQP signaling pathway in the stomach, MTL and GAS levels in the serum, AQP1 and AQP3 expression in the duodenum, and AQP3 and AQP4 expression in the colon.

Влияние сукцинатсодержащего препарата на лейкоцитарный состав крови крыс в покое и при плавании с грузом в тесте «до отказа»

This paper studied the dynamics of the blood leukocyte composition in Wistar male rats at rest and when swimming with a weight before and after being administered a succinate-containing drug (Suc, meso-2,3-dimercaptosuccinic acid). Two control groups of animals kept in standard vivarium conditions were selected: those that received Suc 12 hours before the examination (VivC+Suc) and those that did not receive it (VivC). Similarly, two groups of animals were formed that were swimming with a load (4 % of their body weight) to exhaustion: those that received the drug 12 hours before the test (Swim4%+Suc) and those that did not receive it (Swim4%). Unidirectional shifts characterizing the morphofunctional state of white blood cells under experimental conditions were detected. In VivC+Suc animals, compared to VivC, we found an increase in the number of leukocytes due to the growing number of eosinophils and monocytes, large lymphocytes and microlymphocytes with a relative decrease in the number of small lymphocytes and an unchanged level of granulocytes with a tendency towards a decrease in the number of stab neutrophils. In the Swim4%+Suc group, compared to the Swim4%, changes in the number of white blood cells and their subpopulation composition manifested themselves in a similar way to the redistribution of immunocytes identified in the control groups. The increase in the neutrophilto-lymphocyte ratio in the Swim4%+Suc group as an indicator of stress tolerance corresponded to the increase in the swimming time of rats by the factor of 2.8. The differences in the blood cell composition between the VivC+Suc and VivC groups are viewed as the influence of Suc on the body’s preparation to the fulfilment of the protective function under physical load, since the distribution pattern of the blood leukocyte composition in rats from the VivC+Suc group is very similar to that of the Swim4%+Suc group. The practical significance of this study is associated with the search for new biologically active substances that optimally influence the immune system of animals under increased load. New data on the mechanism of blood redistribution in animals under the action of Suc before the swimming test can be used to study the manifestation patterns of acute adaptation effect. For citation: Rubtsova L.Yu., Mongalev N.P., Vakhnina N.A., Shadrina V.D., Chupakhin O.N., Boyko E.R. Effect of a Succinate-Containing Drug on the Blood Leukocyte Composition in Rats at Rest and During a Weight-Loaded Forced Swimming Test. Journal of Medical and Biological Research, 2021, vol. 9, no. 2, pp. 182–191. DOI: 10.37482/2687-1491-Z056

Mechanism of different processed products of Codonopsis pilosula on spleen deficiency rats based on 1H-NMR metabonomics

Based on1 H-NMR metabonomics,the effects of Codonopsis pilosula,rice-fried C. pilosula and honey-fried C. pilosula on spleen-asthenia rats were compared,and the mechanism was discussed in this study. The rat model of spleen deficiency was established by weight-bearing swimming and fasting every other day. The effects of different processed products of C. pilosula on the body weight and swimming time of rats were observed. At the end of administration,the gastrocnemius muscle of the right leg of rats was collected and detected by1 H-NMR,and the mechanism of different processed products of C. pilosula in improving spleen deficiency was preliminarily investigated by multivariate statistical analysis. The results showed that C. pilosula,honey-fried C. pilosula and rice-fried C. pilosula could significantly prolong the swimming time( P<0. 05). There was no significant difference in the body weight of rats with spleen deficiency. The results of metabonomics showed that honey-processed C. pilosula could significantly decrease levels of leucine,isoleucine,alanine,acetate,glutamate,succinate,anserine,dimethylamine,dimethylglycine,creatine,phosphorylcholine,glycerophosphorylcholine,taurine,inosine,fumate,hypoxanthine and lactate,but increase levels of glucose,glycine,compared with model group. Therefore,honey-fried C. pilosula has the best efficacy on spleen deficiency syndrome in rats by regulating glycometabolism,amino acid metabolism,lipid metabolism and nucleotide metabolism.

Effect of moxibustion at Shenque (CV 8) on immune system in rats with different degrees of exhaustive exercise

To investigate the effect of moxibustion at Shenque (CV 8) on the immune system in rats with different levels of exhaustive exercise. Fifty-six male Sprague-Dawley (SD) rats were randomly divided into a blank group (n=8), an exhaustive group (n=24), and a moxibustion group (n=24). The exhaustive group was randomly divided into a 1-time exhaustive group, a 4-time exhaustive group and a 7-time exhaustive group, with 8 rats in each group. According to the treatment time, the moxibustion group was randomly divided into a 1-time moxibustion group, a 4-time moxibustion group and a 7-time moxibustion group, with 8 rats in each group. Rats in the exhaustive groups and the moxibustion groups were subjected to replicating the exhaustive swimming models. Rats in each moxibustion group received mild moxibustion for 15 min immediately after the exhaustive modeling, once every other day. Twenty-four hours after the corresponding exhaustive exercise, the rats in each group were tested for the levels of serum immunoglobulin (Ig) G, IgA, IgM and acid phosphatase (ACP), and the morphological changes of spleen tissues were observed. The level of IgA was detected by immunoturbidimetric assay, and the levels of IgG, IgM and ACP were detected by enzyme-linked immunosorbent assay (ELISA). Compared with the 1-time exhaustive group, swimming time of rats in the 4-time exhaustive group was significantly prolonged (P<0.01), and swimming time of rats in the 7-time exhaustive group was significantly shortened (P<0.01). Compared with the 7-time exhaustive group, exhaustive swimming time of rats in the 7-time moxibustion group was significantly prolonged (P<0.01). Compared with the blank group, the IgG level in the 1-time exhaustive group was significantly decreased (P<0.01), and the levels of IgG, IgA and IgM in the 4-time exhaustive group and the 7-time exhaustive group were all significantly decreased (P<0.05 or P<0.01), while the ACP level was increased significantly (both P<0.01). Microscopically, the number of splenic corpuscles in the 1-time exhaustive group was reduced; the center of some splenic corpuscles in the 4-time exhaustive group was damaged; the number of splenic corpuscles in the 7-time exhaustive group was reduced, and there was no obvious germinal center. Compared with the 4-time exhaustive group, the IgA level in the 4-time moxibustion group was significantly increased (P<0.01), and the ACP level was significantly decreased (P<0.01). Compared with the 7-time exhaustive group, the levels of IgG, IgA and IgM in the 7-time moxibustion group were significantly increased (all P<0.01), and the ACP level was significantly decreased (P<0.01). Microscopically, the number of splenic corpuscles in the 1-time moxibustion group was reduced; the center of some splenic corpuscles in the 4-time moxibustion group was damaged together with hyperplasia of some splenic corpuscles; blast cells were proliferated in the center of some splenic corpuscles in the 7-time moxibustion group. Moxibustion at Shenque (CV 8) can improve the levels of IgG, IgA and IgM, reduce the ACP level, repair damaged spleen tissues, and enhance the immunity of the body to some extent in the long-term fatigue rats.

Effect of moxibustion at Shenque (CV 8) on free radical metabolism in rat’s hippocampus after different degrees of exhaustive exercise

To investigate the effect of moxibustion at Shenque (CV 8) on free radical metabolism in rat’s hippocampus after different degrees of exhaustive exercise. A total of 72 male Sprague-Dawley (SD) rats were randomly divided into a normal group (n=8), a model group (n=32) and a moxibustion group (n=32). According to the times of modeling or treatment, the model group was further randomly divided into different subgroups of a 1-time model subgroup, a 4-time model subgroup, a 7-time model subgroup and a 10-time model subgroup (n=8); the moxibustion group was also further randomly divided into different subgroups of a 1-time moxibustion subgroup, a 4-time moxibustion subgroup, a 7-time moxibustion subgroup and a 10-time moxibustion subgroup (n=8). Rats in both model and moxibustion subgroups were subjected to establishing the swimming exhaustive model. Rats in each moxibustion subgroup received mild moxibustion at Shenque (CV 8) for 15 min immediately after modeling, once every other day. The concentration of malic dialdehyde (MDA), as well as the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC) in rat’s hippocampus in each group were detected 24 h after the exhaustive exercise. Compared with the 1-time model subgroup, the exhaustive swimming time of rats was significantly prolonged in the 4-time model subgroup (P<0.01), while it was significantly shortened in the 7-time and 10-time model subgroups (both P<0.01). Compared with the matched model subgroup, the exhaustive swimming time of rats in the 7-time and 10-time moxibustion subgroups was significantly prolonged (both P<0.01). Compared with the normal group, the MDA concentration was increased significantly (P<0.01), and the activities stress response of SOD and T-AOC were increased in the 1-time model subgroup (both P<0.05); the MDA concentration was increased (all P<0.01), and the activities of SOD, GSH-Px and T-AOC were decreased differently (P<0.05 or P<0.01) in the 4-time, 7-time and 10-time model subgroups. Compared with the matched model subgroup, the concentration of MDA was significantly reduced (P<0.05 or P<0.01), and the activities of SOD, GSH-Px and T-AOC were significantly increased in the 4-time, 7-time and 10-time moxibustion subgroups (all P<0.01). Moxibustion at Shenque (CV 8) can improve the fatigue status of the body after long-term exhaustive exercise by regulating free radical metabolism in rat’s hippocampus. To some extent, this provides an experimental basis for moxibustion at Shenque (CV 8) against exercise-induced fatigue.

Therapeutic effects of Dunhuang Liaofengxushouruo decoction on chronic heart failure in rats

To observe the therapeutic effects and mechanism of Dunhuang Liaofengxushouruo decoction (LXD) (Traditional Chinese Medicine) on chronic heart failure(CHF) in rats. Forty-eight male Wistar rats were randomly divided into normal group(n=8):model group, captopril group and LXD(Traditional Chinese Medicine) high, medium and low dose group. Except the normal group, the rats were intravenous injected with adriamycin 2.5 mg/kg in one day for 6 weeks, the captopril rats were intragastric administrated by captopril 25 mg/kg, LXD high, medium and low dose groups were intragastric administrated by LXD of 80, 40, 20 g/kg for 6 consecutive weeks. The rats breathing, coat color, activity, body weight(BW) and time of exhaustive swimming were measured; Heart rate, mean arterial pressure (MAP), left ventricular systolic pressure (LVSP), left ventricular end diastolic pressure (LVEDP), maximal rate of left ventricular pressure (+dp/dtmax or -dp/dtmax)of each rat were examined by Power Lab. The levels of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) were measured; The rats were sacrificed and hearts removed for separation of left and right ventricle, the antioxidant activity and ventricular mass index were measured, left ventricular myocardium was administrated by 4% paraformaldehyde, HE staining, morphological changes were observed under microscope. Body weight of each group decreased, and time of exhaustive swimming decreased after modeling (P<0.01). At 28 days after administration, BW in high and middle dose of LXD groups were increased and the swimming time of rats in LXD high dose group was increased (P<0.05).At 42 days, BW in all of LXD groups were increased and the exhaustive swimming time of high and middle dose of LXD were prolonged (P<0.05), MAP was decreased and LVSP, +dp/dtmax or -dp/dtmax were increased in LXD high and middle groups. The LVEDP was decreased in high dose of LXD group(P<0.05,P<0.01). The levels of creatine kinase (CK) and aspartate aminotransferase (AST) in middle and low dose of LXD groups were decreased(P<0.05,P<0.01), and the serum levels of IL-6, TNF-α and malondialdehyde (MDA) in serum in LXD high and middle dose groups were lower. The activities of superoxide dismutase (SOD) in serum were increased in all of LXD groups, and the LVMI and RVMI were decreased in high and middle dose of LXD groups(P<0.05,P<0.01). The pathological results showed that myocardial fiber arrangement and myocardial interstitial edema phenomenon were obviously improved in high dose of LXD group and CMD decreased. Therapeutic effect of LXD on CHF by doxorubicin-induced in rats is confirmed, the mechanisms are associated with improved hemodynamics and myocardial tissue.

Study of the Extraction and Hypolipidemic Mechanism of Steviosides from &lt;em&gt;Stevia rebaudiana&lt;/em&gt; Leaves

In order to understand the hypolipidemic mechanism of steviosides from Stevia rebaudiana leaves, we optimised ratio of solid to liquid, extraction temperatures, extraction times, time to obtain optimal extraction conditions. Under the optimal condition (solid to liquid 1:20, extraction temperature 80C, and extraction times 4h, time 4), the experimental yield of steviosides was gave the best results (8.637±0.27%). The SVS-2 were obtained by a DEAE-52 cellulose column and Sephadex G-15 column chromatography. The SVS-2 was characterised through FT-IR spectroscopy, NMR spectroscopy, HPLC-PAD-MS analysis by comparison with a stevioside standard. In vitro test, the steviosides can decrease liver TC, TG and serum TG, TC level and increased swimming time of rats fed with high-fat diets. Therefore, the results suggest that steviosides had a high hypolipidemic activity and could be used as a potential therapeutic agent for hyperlipidemia.

The effect of nicotine on the swimming speed of pre-trained rats through a water alley.

In sessions of ten runs each, swimming time of rats through a 4 m long water alley was measured. Four doses of nicotine (0.05; 0.1; 0.2; 0.4 mg/kg given intraperitoneally 30 minutes before testing) were tested in sessions with a braking load on the tails of the animals either in all 10 runs of a session, or in every second run, or in none of the 10 runs. Regardless of the swimming condition, nicotine produced a considerable, and at doses of 0.1 mg/kg and over, significant decrease of performance in the first two runs. From the third to the 10th run, the changes caused by nicotine were smaller and differed depending on the swimming conditions.

Effect of chlorpromazine on swimming time of rats at different temperatures.

SummaryWhen rats are swimming at 19 or 28°C, swimming time is markedly reduced by chlorpromazine (10 mg/kg) treatment. This difference is not due to differences in body temperature but is probably caused by sedation and muscular paralysis caused by this drug. At 9°C the detrimental effect of bath temperature on swimming time is so marked that chlorpromazine fails to display any action whereas at 32°C the stress is so small as to allow the animal to perform as well even when treated with chlorpromazine.