[Experimental study of the effects of citalopram, olanzapine, and their combinations in tests for antipsychotic, antidepressant and anxiolytic activities of drugs].

The effects of citalopram, olanzapine and their combinations were studied in tests on outbred SHR male mice. The locomotor activity was determined in the open field, the antidepressant effects - in the tail suspension test, the anxiety-like behavior- in the light-dark transition test; in addition, the antidopaminergic effects of drugs and their combination were evaluated using the apomorphine-induced stereotypy. The results indicate that olanzapine inhibits locomotor activity in all behavioral tests, whereas citalopram alone has no significant effect and does not modify the action of olanzapine.

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.

Effect of M4-cholinoceptor blockade on haloperidol-produced catatonic syndrome in rats.

We studied the relationship between the efficiency of muscarinic receptor antagonists in preventing haloperidol-induced catatonia and their activity in tests for the interaction of ligands with various subtypes of muscarinic receptors (M1-M4) in rats. Mathematical modeling showed that affinity of the ligand for M4 receptors positively affects its ability to correct extrapyramidal disorders (catatonic syndrome) produced by haloperidol, while affinity for M2 receptors had a negative effect on this characteristic.

Qualitative assessment of selective blockade of M(4)-cholinoreceptors in the whole organism.

Quantitative assessment of selective blockade of M4-subtype muscarinic receptors was performed by the number of pilocarpine-induced movements of lower jaw in rats. Three antagonists (atropine, cyclodol, and glipin) were used in the experiments. Glipin produced the most potent blockade of M4 receptors in the whole organism compared to other test antagonist.