Inhibitory action of calcium antagonists on ATP-dependent calcium uptake by the renal cortical microsomes.
Effects of Ca2+ antagonists, verapamil and diltiazem, on uptake and release of Ca2+ by microsomes of the renal cortex were studied. Verapamil inhibited the ATP-dependent Ca2+ uptake by renal microsomes. Addition of 0.8 mM verapamil was required to produce 50% inhibition of the ATP-dependent CA2+ uptake. Diltiazem also depressed the Ca2+ uptake was not due to an increased permeability for Ca2+, since release of Ca2+ from the microsomes was not significantly affected by either drug. It is proposed that verapamil and diltiazem inhibit Ca2+ transport by interfering with an active process of Ca2+ accumulation in microsomes of the renal cortex.
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D001552:Benzazepines / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D003864:Depression, Chemical; D004110:Diltiazem / Q000494:pharmacology*; D066298:In Vitro Techniques; D007672:Kidney Cortex / Q000166:cytology*; D008297:Male; D008861:Microsomes / Q000378:metabolism*; D051381:Rats; D014700:Verapamil / Q000494:pharmacology*
D001552:Benzazepines; D000255:Adenosine Triphosphate; D014700:Verapamil; D004110:Diltiazem; D002118:Calcium