Rossiiskii fiziologicheskii zhurnal imeni I.M. Sechenova最新文献

Nonopioid stress-induced analgesia is the consequence of activation of CB1 receptors by the increased level of 2-arachidonoyl glycerol, anandamide in the periaqueductal gray matter in the midbrain. The activation of cannabinoid CB1 receptors inhibits stress-induced ulcerogenesis due to the strengthening of the antioxidant defense of the gastric mucosa. CB1 receptor antagonists promote an increase in ACTH and corticosterone concentrations in the blood of intact animals, the knockout of the gene encoding the CB1 receptor exhibits the same effect. Antagonists of CB1 receptors enhance the stressor elevation of ACTH and corticosterone levels in the blood of experimental animals. It was found an increase in stress-induced elevation of corticosterone and ACTH levels in the blood of mice with a knockout of the gene encoding the CB1 receptor. An increase in the endogenous anandamide level or disturbance of the reuptake of endogenous cannabi-noids after application of pharmacological agents promotes reducing corticosterone level in stressed animals. Consequently, endogenous cannabinoids inhibit basal and suppress stress-induced activity of the hypothalamic-pituitary-adrenal axis. The indicated regulation is carried out on the level of the hypothalamus, pituitary and adrenal cortex. Stimulation of central cannabinoid receptors leads to an activation of the sympathetic system. The activation of peripheral CB1 receptors leads to inhibition of norepinephrine release from sympathetic terminals and epinephrine release from the adrenal glands. The endogenous CB1 receptor agonists play an anxiolytic role and prevent the occurrence of pathological anxiety.

In experiments on white rats with different thyroid status (thyroidectomy, euthyroidism, hyper- and a thyrotoxicosis) in conditions in situ the relationship between the severity of functional parameters of the tibialis anterior muscle and individual level of circulating free triiodothyronine was learnt. The latent period of muscle contraction, the average and maximum speed of its contraction were determined. A comparative quantitative analysis of the values of indicators of the contractile function of the tibialis anterior muscle in euthyroid and thyroidectomy rats allowed to evaluate the «thyroid contribution) of free triiodothyronine in the functional state of the native skeletal muscle, which formed to 15% for the latency reduction period, 12 % for the average speed of contractile act and 8% for of the maximum speed of muscle contraction. It is shown that in rats if the control group at the beginning of the scale of triiodothyronine concentration (2.2-4.9 pmol/L) hormone activity is expressed weakly, and in the range of 5.2-7.6 pmol/L is greatly increased (up to 11 times). It was established that the positive effect of triiodothyronine is preserved far beyond of the physiological norm of hormone concentration. It is allowed to speak about the existence of an extended corridor of hormone activity. On the base of the analysis of the degree of severity of the physiological parameters of the muscle contraction curve from circulating level of triiodothyronine in rats with different thyroid status (0.1-45 pmol/L) constructed of functional activity of free triiodothyronine. This curve consists of 7 different zones which are located in different sectors of the scale of concentration.

Under a progressive growth of acute hypoxia the effect of high systemic levels of proinflammatory cytokine interleukin-1 Р (IL-1Р) were studied the reactions of the cardiorespiratory system of anesthetized Wistar rats. The results suggest a negative effect of IL-1 Р on the control mechanisms the respiratory and cardiovascular system, which was reflected in the reduction of resistance to acute hypoxia and the ability to spontaneous autoresuscitation after apnea in posthypoxic period, as well as in the development of circulatory collapse. It is assumed that the basis of the resistance mechanisms of the body to reduce the hypoxic exposure is multifactorial effects of increased levels of IL-1 Р, activation of HIF-1 a and NO production in the operation of the systems responsible for maintaining oxygen homeostasis.

We have studied the effect of Р-endorphin (an endogenous opioid peptide) on the functional characteristics of isolated rat heart. In physiological concentrations (6.3 X 10-10 M) Р-endorphin induces a negative inotropic effect, accompanied by a slight decrease in the heart rate, and has no effect on the perfusion pressure of the coronary vessels. It is shown that the effect of Р-endorphin is mediated by 5-opioid receptors. ATP-dependent K+-channels contribute the greatest contribution to the implementation of the effect of Р-endorphin on the isolated heart of a rat. The role of voltage-dependent K+-channels and NO-mediated mechanisms in the implementation of the effects of Р-endorphin is minor.

We performed a comparative study of the effect of original domestic derivatives of 3-oxypyri-dine and succinic acid (emoxipine, reamberin and mexidol) on measures from «sucrose preferen-ce» test which is used for assessment of hedonic behavior in rats. а-lipoic acid (а-LA) and amit-riptylin were used as reference medications. For the modeling of anhedonia rats received dexa-methasone (5 mg/kg subcutaneously). We established that threefold administration of emoxipine, reamberin and mexidol in doses that are equivalent to therapeutic range in humans had antianhe-donic effect and increased the measures of «preference» and absolute sucrose consumption. This effect was demonstrated in animals that did not receive dexamethasone as well as in rats with dexamethasone-induced anhedonia. Maximal intensity of antianhedonic effect of 3-oxypyridine and succinic acid derivatives was noted after the previous administration of dexamethasone. In rats that did not receive dexamethasone, succinate-containing medications (reamberin and mexidol) exceeded the isolated 3-oxypyridine derivative (emoxipine) in their antianhedonic potential. In case of previous dexamethasone administration 3-oxypyridine and succinic acid derivatives demonstrated equivalent antianhedonic effect that exceeded the effect of reference medications (а-LA and amitriptylin).

Functional parameters and degree of myocardial damage by ischemia-reperfusion model of isolated heart were investigated during acute experiments on rats with an antibiotic-induced intestinal dysbiosis after administration of the probiotic strains of Enterococcus faecium L3. Administration of antimicrobial drugs has resulted in an increased heart rate and in an increase in coronary flow of isolated heart. Administration of enterococci after the global ischemia has caused rats to have a decrease in diastolic pressure, increased systolic and pulse pressure, and an increased intensity of coronary flow. The article presents data on changes in the composition of the intestinal microbiota and the immune system that was previously obtained in studies based on this experimental model.

The experiments were performed on Wistar male rats, which were subjected to continuous cold exposure (+4 °C, 4 weeks). It has been established that this exposure is not a chronic stress. It has been shown that prolonged cold impact causes cold adaptation to cold and has the infarct-limi-ting effect.

The study of the electrical activity of the sportsmen-swimmers' heart has been carried out during ventricular repolarization under short-term acute moderate normobaric hypoxia. It was revealed that acute hypoxia leads to a significant decrease of the duration of the early ventricular repolarization immediately after hypoxic exposure, of the duration of the late repolarization - at last minutes. The structural change of ventricular repolarization of the heart of the athletes surveyed was shown based on the changes in amplitude-temporal characteristics of the extrema of the heart electric field during the ventricular repolarization of the heart upon acute hypoxic exposure.

Introducing of urgent relearning in radial maze, consisting of one or two shifts of reward position in raw without any gap between behavioral sessions, resulted to inability of animals to use optimal navigational strategy to find preferable reward in maze while keeping responding to int-ra-maze stimuli. Procedural introducing of time-out between tested behavioral sessions, which was accompanied by sleep generated naturally or induced by injection of neuropeptide ACTH 18-39, resulted to considerable improvement of relearning in radial maze as well as reducing per-severative behavior and attempts to refuse from responding. The data obtained demonstrate the important role of sleep for successful urgent relearning in radial maze and preventing possible neurological disorders.

The review presents facts telling about the involvement of RNA of lymphocytes into regulation of proliferation and differentiation of cells in various tissues. There are considered: transport mechanisms of exogenous RNAs in cells, the role of non-coding RNAs molecules in the regulation of embryonic and postnatal morphogenesis. The long non-coding RNAs and microRNAs of T-lymphocytes are characterized, also there is made a comparative analysis of different microR-NAs expression in T cells and the regulatory effects of these molecules in reparative processes. There are described the RNA technologies, stimulating the anti-tumor immunity and regeneration of damaged tissues used in clinical practice, and also the perspectives of creating new treatments based on the use of RNA preparations.