European Journal of Biomedical and Pharmaceutical Sciences

PRESENCE OF SEROTONERGIC 5HT4-TYPE RECEPTORS IN BROILER’S SMALL INTESTINE

Mujezinovi? Indira, Smajlovi? Ahmed, *Katica Muhamed, Duki? Behija and Gradaš?evi? Nedžad

ABSTRACT

The aim of the present study was to try to determine the possible distribution of 5-HT4 receptors in small intestine of broilers (duodenum, jejunum and ileum). The disturbances of bowel function are common in broilers and if we know that mentioned dysfunction cause great loss to the poultry industry, due to the high mortality, the results of our research could form the basis for the introduction of new drugs in the pharmacotherapy of this species. Investigation were carried out on isolated smooth muscle of the circular and longitudinal layer of the broilers small intestine (strip dimnesion 3-4 mm x 2 cm). The muscle strips were placed in an isolated organ bath. The mechanical activity of the preparations were recorded via an isotonic force transducer coupled to a pen recorder. This was done following the addition of serotinin (nonselective 5-HT agonist), 2-Me-5HT (5-HT3 agonist) and Y-25130-hydrochloride (selective 5-HT3 antagonist). The sensitivity of the tissues to acetylcholine was tested before starting the experiments. The research established a presence of serotonergic 5HT3 type receptors within the smooth musculature of the small intestines of broilers (COBB 500). The 5HT3 type receptors were present in smooth muscles of duodenum, jejunum and ileum, especially in longitudinal smooth muscles since this layer reacted even to low serotonin concentration (10-6). In the light of these findings, we suggest that investigated substances may have considerable physiological and therapeutic implications in disturbed function of small intestine of broiler’s.

Keywords: Broilers, serotonin, serotonergic receptors, isolated smooth muscle, small intestine.