Farmakologiia i toksikologiia最新文献

The antiheparin activity and acute toxicity of the copolymer of 1-vinyl-3-methyl inidazol iodide (VMII) with diethyl ether of maleic acid (DEMA) were investigated. It was shown that the injection of DEMA group to the molecule of VMII polymer was adequate for storage of a high antiheparin activity of the polymer with the structure. This composition of the copolymer has a low acute toxicity and high selectivity to heparin in the blood. Thrombocytopenia effect is absent.

The effects of yohimbine and idazoxane (0.5 and 5 mg/kg, intravenously) on the systemic and regional hemodynamics were studied in conscious Wistar rats by the microsphere technique. The both drugs induced an elevation of the arterial blood pressure and the heart rate. The administration of yohimbine and idazoxane in a dose of 0.5 mg/kg produced a more pronounced increase in the cerebral and coronary blood flow that a higher dose (5.0 mg/kg). The blood flow in the small intestine, kidneys and testis was decreased by a high dose of the studied alpha-blockers. It was suggested that the direct action of alpha 2-blockers on the vessel smooth muscle cells in responsible for the increase in the blood flow whereas blockade of alpha 2-receptors on the sympathetic terminals produces the decrease in the blood flow.

Phencarol, a blocker of H1-histamine receptors, is used as an antihistaminic agent. The antiarrhythmic effect of phencarol was detected and studied on experimental models of arrhythmias in non-anesthetized rabbits in a dose of 5 mg/kg intravenously. The drug was shown to possess the pronounced antiarrhythmic and protective properties on the models of calcium-chloride-, adrenaline- and strophanthine-induced arrhythmias and to exert no influence on aconitine-induced arrhythmia. Phencarol was demonstrated to have no cardiodepressive effect.

In the experiments on Wistar rats to whom heparin was injected intravenously in the tail vein in doses of 50, 100 and 250 U, there were studied the colony-forming ability of the hemopoietic cells, the precursors of the bone marrow, and the colony-stimulating activity of the plasma of the heparinized animals 1, 3, 6, 12 and 24 hours after the drug administration. Heparin was found to increase the proliferative activity of the committed myelopoietic cells-precursors on a diffusion microchamber (GM-CFUdc) stimulating the mononuclears and elevating the level of the colony-stimulating activity of the plasma of the experimental animals.

The experiments on 286 mice of two lines (SHR and C57BL/6) showed that 3-indoipyruvate, a natural keto analogue of tryptophan and a precursor of serotonin and kynurenic acid) possesses the selective dose-dependent (100-500 mg/kg, intraperitoneally) protective effect against quinolinate-induced convulsions. At prolonged administration (50-100 mg/kg for 10 days twice a day) its efficiency drastically increased. It is supposed that the mechanism of the anticonvulsant action of 3-indolpyruvate involves an enhancement of synthesis of kynurenic acid, a blocker of N-methyl-D-aspartate receptors, and at chronic administration--also an increase of sensitivity and density of these receptors.

The data on the pharmacological effects of xanthines and their use in pharmacotherapy, particularly, in regulation of cellular hemostasis to correct disorders of microcirculation are summarized. The possible mechanisms of hemostasis regulation by xanthines and the most promising ways of search for new antiaggregation drugs in this series are considered.

The experiments on albino rats demonstrated that antidepressants pyrazidol, imipramine, incazane, moclobemide and to a lesser degree azaphen reduce the amnesic effects of electroshock and scopolamine in the rats with the acquired conditioned reaction of passive avoidance. The studied antidepressants decrease also the disturbing action of alcohol on the learning of rats of the conditioned reaction of active avoidance.