Inhibitory effects of propranolol on the calcium current of Helix neurones.
1 Calcium current (ICa) and potassium current (IK) in isolated nerve cell bodies of Helix aspersa were independently separated after suppression of Na+ and K+ currents, and Na+ and Ca2+ currents, respectively. The suction pipette method was used. Under voltage clamp conditions, the effects of propranolol on both the ICa and IK were examined. 2 Propranolol inhibits the ICa at relatively low concentrations (10(-6)-10(-5) M). The inhibitory action was dose-dependent. 3 The IK was moderately suppressed by the drug at high concentrations (10(-5)-5 X 10(-1) M). 4 Results provide evidence for a new aspect of the pharmacological action of propranolol on the excitable cell membrane.
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D006372:Helix, Snails; D007473:Ion Channels / Q000187:drug effects*; D009474:Neurons / Q000502:physiology*; D011188:Potassium / Q000378:metabolism; D011433:Propranolol / Q000494:pharmacology*
D007473:Ion Channels; D011433:Propranolol; D011188:Potassium; D002118:Calcium