[Effect of vasotocin and prostaglandin E2 on absorption of water and ions in the large intestine of a grass fog].

In experiments on the frog Rana temporaria L. isolated colon, it has been shown that the rate of fluid absorption from the lumen is the highest when the lumen contains a hypotonic solution (22.5 mOsm/kg H2O), whereas the rate is lower in case of mucosal Ringer solution (225 mOsm/kg H2O). 10 nmole arginine-vasotocin rises the hypotonic fluid absorption, while 0.1 mumole prostaglandin E2 reduces the fluid absorption. Water content in the colon wall is the highest at mucosal hypotonic Ringer solution. 0.1 mumole prostaglandin E2 decreases hydration of the colon tissue. Secretion of prostaglandins E1 and E2 into the extracellular fluid of the colon has been established. The data obtained indicate participation of vasotocin and prostaglandin E2 in regulation of fluid absorption in the frog colon.