Regulation of voltage-dependent Ca2+ channels of neuronal cells by chronic changes in membrane potential.
The regulation of voltage-dependent Ca2+ channels by chronic changes in membrane potential was studied by measuring the binding of [3H]nitrendipine to membranes from PC12 pheochromocytoma cells. Depolarization of the cells by elevation of extracellular K+ caused up to a 45% loss of [3H]nitrendipine binding sites within 4 days without any change in Kd. Repolarization of the cells caused a return to control binding within 1-2 days, showing that either decreases or increases in membrane potential can cause reversible changes in [3H]nitrendipine binding sites.
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects / Q000378:metabolism*; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000378:metabolism*; D009568:Nitrendipine / Q000378:metabolism; D009861:Onium Compounds / Q000378:metabolism; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D014320:Triphenylmethyl Compounds / Q000378:metabolism
D007473:Ion Channels; D009861:Onium Compounds; D014320:Triphenylmethyl Compounds; C011561:triphenylmethylphosphonium; D009568:Nitrendipine; D011188:Potassium; D002118:Calcium