Interference of sodium with [3H]-nitrendipine binding to cardiac membranes.
Interference of sodium with [3H]-nitrendipine binding was studied on membrane homogenates from guinea-pig skeletal muscle, cerebral cortex and left cardiac ventricle. [3H]-nitrendipine binding on homogenates from cerebral cortex and skeletal muscle was unaffected by Na+ (35 and 140 mEql(-1]. On the other hand, for the myocardial receptors, addition of Na+ resulted in an increase in IC50 of nitrendipine. Simultaneously, for the myocardial preparations, saturation curves showed a decrease in [3H]-nitrendipine affinity and an increase in the number of binding sites.
Schwartz
J
J
Velly
J
J
D000818:Animals; D001667:Binding, Competitive / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000378:metabolism*; D002540:Cerebral Cortex / Q000378:metabolism; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects; D066298:In Vitro Techniques; D007700:Kinetics; D008566:Membranes / Q000378:metabolism; D009132:Muscles / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism*; D009543:Nifedipine / Q000031:analogs & derivatives* / Q000378:metabolism; D009568:Nitrendipine; D012964:Sodium / Q000494:pharmacology*
D002121:Calcium Channel Blockers; D009568:Nitrendipine; D012964:Sodium; D009543:Nifedipine