Effect of M2 muscarinic receptor blockade in rats with haloperidol-produced catatonic syndrome.

We studied the functional role of individual subtypes of muscarinic cholinoceptors in the pathogenesis of neuroleptic parkinsonism in rats. Blockade of M4 receptors prevented the development of extrapyramidal disorders, which was abolished by simultaneous blockade of M2 receptors. The data suggest that various subtypes of muscarinic receptors are involved in the regulation of dopamine concentration.

Mathematical analysis of subtypes of muscarinic receptors modulating heart and respiratory rhythms in rats.

Mathematical analysis of the data obtained in experiments on the whole organism revealed that blockade of M(2)-cholinergic receptors increased both heart and respiratory rates. Blockade of M(1)-cholinergic receptors alleviated tachycardia induced by M(2)-receptor blockade.

[Toxicological study of materials for artificial heart valves].

The toxicological study was performed in order to establish the optimum carbon thromboresistant coat of titanium in creating new constructions of the artificial heart valves under conditions of chronic experiments in albino rats. Fine samples of carbon coats made by different techniques were studied. The biological activity of only one coat made by the method of ionoplasmic spraying with using chemically pure carbon target was established.