Fiziologicheskiĭ zhurnal最新文献

It has been established that hippocampus, enthorhinal cortex, amygdala and substantia nigra (pars reticulata) lesions before head injury lead to a decrease of kainic acid-induced behavioral and electrographic seizure expressions. It can be concluded that after head injury the activation of limbic structures excitability due to excitation of "inputs" to these formations takes place. The obtained data indicate the significant role of nucleus caudatus in activation of posttraumatic brain excitatory mechanisms.

The content of prostaglandins (Pg) E, F2, 6-keto-F1 alpha, thromboxane B2 has been examined in funic blood serum and peripheral blood of 172 newborns. 38 neonates endured chronic hypoxia in the antenatal period, 42 had acute hypoxia during labour and in 39 acute hypoxia during labour developed against a background of chronic intrauterine hypoxia. The control group consisted of 53 infants that were not subjected to hypoxia during antenatal and intranatal periods. In control group in the dynamics of early neonatal period a decrease of PgE, PgE2 alpha concentration and an increase of 6-keto PgF1 alpha, TxB2 were observed. The PgE level was determined to be higher in infants with chronic hypoxia and acute hypoxia than that in the control group. In acute hypoxia the PgE concentration did not differ from that in the control group. PgF2 content was decreased in infants with chronic hypoxia and increased with acute one. The PgF alpha 1 level was noticed to decrease in chronic hypoxia and acute hypoxia against the chronic background. Thromboxane B2 concentration was increased in all the types of hypoxia. The 6 keto PgF1 alpha/TxB2 ratio decreasing in infants with all the types of hypoxia underwent the most pronounced changes. The largest deviations were marked in infants with associative hypoxia. The revealed dynamics of prostaglandin changes in the postnatal period in the control group is similar to the dynamics that reflects the course of stress-reaction under the influence of other stimuli. It permits affirming that there are common mechanisms of the prostaglandin system response to stress.(ABSTRACT TRUNCATED AT 250 WORDS)

The content of stable metabolites of prostacyclin and thromboxane A2 in the rabbit myocardium in normal conditions and after single izadrin injection (comparison of survived and dead animals) has been comparatively analyzed. It has been shown that in all the cases izadrin injection induces the synthesis of these prostaglandins. But the cases with lethal outcome are characterized by predominance of the thromboxane-synthetase activity. The revealed peculiarities of prostaglandins synthesis in myocardium need experimental check on the isolated heart.

The functional and structural changes in the liver of white rats both low- and high-resistant to hypoxia, have been studied using the biochemical and morphological methods. It has been found that intensity and degree of the liver injury in experimental toxic hepatitis depend on the systemic resistance to hypoxia. The functional and morphological changes in the injured liver have been found to be less pronounced in the high-resistant rats as compared with those in the low-resistant animals.

Ultrastructural changes in the lungs and kidneys in the dynamics of endotoxin shock have been studied in experiments on rats, rabbits and dogs. It has been shown that in the initial period of shock in the epithelial cells of alveoli and convoluted tubules dystrophic processes take place and simultaneously the vascular permeability increases. In the intermediate period of the endotoxin shock the mesenchymal dystrophy is additionally registered in the lungs, while necrosis of epithelium of some tubules--in the kidneys. The interstitial fibrosis and mitosis of pneumocytes of type II, substituting the respiratory epithelium are revealed in the lungs at the stage of late endotoxemia. The adaptive changes, arising as a result of improving renal hemodynamics are observed in the kidneys.

The experiment on 90 rabbits and 30 rats has been conducted to compare the effect of different regimes of hyperbaric oxygenation (HBO) (pressure of oxygen: 3 ata, 2 ata, oxygen-air mixture: 3 ata and 1 ata, respectively) on the morphofunctional state of intact and ischemic myocardium with experimental infarction. The histoautoradiographic method using 3H-thymidine and 3H-uridine, the precursors of nucleic acids' synthesis, proved a good criterion of viability and activity of the regenerative processes in cardiomyocytes of perinfarction and necrosis-distant zones of the heart. The best effect has been obtained when using HBO regime with oxygen pressure 2 ata, the highest damaging effect--oxygen (3 ata)-air (1 ata) mixture. The use of HBO has prevented the development of necrosis foci and dystrophic changes in the auricles.

Data are presented concerning the basal levels of parathormone and calcitonin and the effect of dihydropyridine derivatives on the characteristics of haemodynamics as well as pancreatic secretory activity in patients with diabetes mellitus. It is shown that in diabetic patients with hypertension a single administration of the drugs induces vasodilatation which causes lowering of systolic and diastolic blood pressure. In patients with diabetes mellitus in combination with hypertension, heart coronary disease and obvious peripheral angiopathy (similar procedure) no peripheral vasodilatation was observed. No negative effects were observed on the compensatory processes (and obviously on pancreatic secretory activity in patients with both insulin-dependent and insulin-independent diabetes mellitus even during long-lasting administration of drugs. A conclusion is made that calcium channel antagonists should be recommended to patients with diabetes mellitus taking into account the state of their peripheral vessels.

The change in alpha-tocopherol content (as an index of the antioxidative organism system mobilization) in the brain, liver, muscles and heart of rats prior to and after total gamma-irradiation with lethal dose has been studied. Prior to the irradiation alpha-tocopheryl-acetate (oil solution), alpha-tocopheryl-phosphate dipotassium salt (water solution), gammaphos (prepared WR 2721, water solution) were introduced into rats. It is shown that water-soluble form of vitamin E is more effective than gammaphos and much more efficient than oil form of alpha-tocopherol.

Polypeptide cytomedine, isolated from renal tissues has been studied for its regulatory effect on hemocoagulation and lipid peroxidation with fluoric intoxication (FI). FI was caused by inoculation of laboratory animals (guinea pigs) with sodium fluoride (100 mg/kg) for 14 days. Following it polypeptide (0.1 mg/kg) was introduced intramuscularly for 7 days. The development of FI was expressed by hypercoagulation delay of fibrinolysis with para-coagulation products appearing in blood decrease of antiaggregation activity of the renal tissue. These phenomena were estimated as manifestations of the first phase of disseminated intravascular blood coagulability (DIC-syndrome). The above reactions proceeded simultaneously with lipid peroxidation activation decrease of the antioxidant protection. The necrotic-dystrophic processes developed in renal and hepatic parenchyma. The renal peptide-cytomedine induced the normalization of lipid peroxidation in blood and renal tissues and fibrinolysis, the decrease in the concentration of para-coagulation products. The pathological changes decreased both in the renal and hepatic tissues. It is possibly, a result of the normalization of secretion and reabsorption in the kidneys. Thus, cytomedine of the kidney exerts a pronounced regulatory and protective effect in the case of acute renal pathology. These results correspond to the conception of the peptidergic organism regulation.

Blood chemiluminescence is a reflection of the free radical oxidation process in every organism. The changes of its intensity, as a consequence of changes in the rate of this process, are connected, in its turn, with the changes, in the functional state of the organism. It is supposed that the differences in the radiosensitivity depend on the conditions in which free radical oxidation processes take place. Therefore, the indices of blood chemiluminescence of intact rats have been studied. The aim of the investigation is to find the correlations between these indices and the survival of animals irradiated with gamma-quantas in doses of 3.5, 7.0 and 9.0 Gr. It is established that the coefficients of the reaction rate (k1, k2 and k3) most reliably correlate with survival, whereas no correlation is observed between the other indices of chemiluminescence and survival.