5-HT4 RECEPTOR BLOCKADE ELIMINATES EXCITATORY RESPONSES OF THE STOMACH CAUSED BY EXOGENOUS SEROTONIN

The purpose of the study is to determine the role of 5HT4-receptors in excitatory responses of the stomach to exogenous serotonin. Experiments were performed in 27 rats under surgical anesthesia, mechanical ventilation, bilateral vagotomy and bilateral transaction of the glossopharyngeal nerve. Gastric mechanical activity was recorded during serotonin adipate infusion to intact animals and on the background of the ongoing actions of cholinergic, adrenergic antagonists and S 39604-the blocker 5-HT4-receptors. Simultaneous blockade of adrenergic and cholinergic receptors did not prevent, but amplify stimulatory effect of serotonin. 5-Ht4 receptor blockades eliminate excitatory reactions. It was concluded that serotoninergic structures exerted their control influence by 5-HT4-receptors.

Serotoninergic structures, serotonin, stomach, 5-HT4-receptors, adrenergic receptors, cholinergic receptors