Athamnah S. Effects of histamine and serotonin on bile secretory function and liver respiration

The thesis is devoted to investigation of the role of histamine and serotonin in bile secretory function and liver tissue respiration. It was found that histamine at 8 mg/kg inhibited the synthesis and hydroxylation of free primary bile acid and oxygen consumption by the liver and increased blood pressure in the portal vein without changing the level of oxygen tension in liver and blood pressure in the arterial vessels. In the presence of histamine H1 receptor blocker tavegil (25 mg/kg), these effects have been abolished. Histamine caused an increase in the concentration of bile phospholipids, cholesterol and its esters. Histamine increased the formation and flow of bile and elevated taurocholate concentration that is produced with the involvement of H1 receptors. Serotonin (10 ?g/kg) caused an increase in conjugation with free cholate taurine and glycine, secretion phospholipids and cholesterol to bile, oxygen consumption by the liver and blood pressure in the portal vein. Serotonin caused an decrease oxygen tension in the liver and blood pressure in the arterial vessels. Blockade of 5-HT2 receptors by ketanserin(3 mg / kg) resulted in the inhibition of serotonin effect on bile secretion and complete suppression of respiration reactions. It is shown that serotonin reduces the amount of bile production, and that this effect persists in the presence of ketanserin.