Modulatory effect of oxytocin and arginine-vasopressin on functional properties of three types of acetylcholine receptors in molluscan neurons
Dyatlov, V.A.
Acta Physiologica Hungarica 76(4): 253-259
1990
ISSN/ISBN: 0231-424X PMID: 1716816 Document Number: 364301
It was found that 10(-7)-10(-8) mol/l oxytocin (OT) or arginine-vasopressin (AVP) applications produced effects on functional properties of three types of acetylcholine (ACh) receptors on various neurons identified in the ganglia of Helix pomatia under voltage clamp conditions. OT and AVP depressed ACh-induced sodium-potassium-calcium current in neuron RBc3 without shift of reversal potential. Our data show that there are two types (subtypes) of ACh receptors which are connected with chloride current in neurons of Helix pomatia. OT decreased ACh-induced chloride current in neuron D4 and enhanced ACh-induced chloride current in neuron D5. These effects of OT were mimicked by the intracellular injection of cyclic AMP or application of isobutylmethylxanthine and an active cyclic AMP analog. AVP as a rule mimicked the effects of OT on functional properties of ACh receptors, but in neuron F8 effects of OT and AVP were independent. The present results suggest that cyclic AMP may be the second messenger mediating the OT- and AVP-induced modulations of functional properties of three types of ACh-receptors.