The effect of oxytocin on potential-dependent calcium current in snail neurons, Helix pomatia.
1. The effect of external application of oxytocin on inward calcium current in dialyzed snail neurons has been investigated under clamp conditions. 2. External application of oxytocin in a dose-dependent manner (Kd 0.9 microM) inhibits inward calcium current in dialyzed neurons of the snail, Helix pomatia. 3. Inhibition of calcium current developed with the time constant of about 2 min. The degree of restoration of calcium current after oxytocin washout depends on duration of oxytocin action. 4. It has been suggested that inhibition of calcium current by oxytocin occurs in two stages, the initial one is more fast and reversible and the second one--more slow and irreversible. The participation of soluble second messengers in the inhibitory effect of oxytocin on calcium current is discussed.
A. A. Bogomoletz Institute of Physiology, Ukrainian Academy of Sciences, Kiev, U.S.S.R.
N I
NI
Kononenko
A D
AD
Shcherbatko
D000818:Animals; D002118:Calcium / Q000378:metabolism / Q000502:physiology*; D000242:Cyclic AMP / Q000494:pharmacology; D003956:Dialysis / Q000379:methods; D004305:Dose-Response Relationship, Drug; D004533:Egtazic Acid / Q000494:pharmacology; D004594:Electrophysiology; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000494:pharmacology; D006372:Helix, Snails; D007424:Intracellular Fluid / Q000378:metabolism; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D010121:Oxytocin / Q000494:pharmacology*; D013696:Temperature; D013997:Time Factors; D014667:Vasopressins / Q000494:pharmacology
C069944:vasopressin, des-Gly-; D014667:Vasopressins; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D010121:Oxytocin; D004533:Egtazic Acid; D000242:Cyclic AMP; D002118:Calcium