Interaction of calmodulin inhibitors and protein kinase C inhibitors with voltage-dependent calcium channels.
We compared the relative abilities of a series of calmodulin inhibitors and protein kinase C inhibitors to influence 45Ca2+ influx through voltage-dependent Ca2+ channels in PC12, a clonal neural cell line. K+-depolarization-dependent 45Ca2+ uptake was reduced by the calmodulin inhibitors calmidazolium, trifluoperazine, W-7, W-13, and W-5 at concentrations comparable to those that affect calmodulin, while the protein kinase C inhibitors polymyxin B and H-7 were weak or ineffective. The Ca2+ channel antagonist properties of calmodulin inhibitors should be considered in interpreting their effects on Ca2+-dependent cellular events.
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002121:Calcium Channel Blockers / Q000494:pharmacology; D002147:Calmodulin / Q000037:antagonists & inhibitors*; D002460:Cell Line; D004586:Electrophoresis; D007473:Ion Channels / Q000187:drug effects* / Q000502:physiology; D051379:Mice; D009994:Osmolar Concentration; D011188:Potassium / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors*; D013268:Stimulation, Chemical
D002121:Calcium Channel Blockers; D002147:Calmodulin; D007473:Ion Channels; D011493:Protein Kinase C; D011188:Potassium; D002118:Calcium