Hulthén U L, Landmann R, Bürgisser E, Bühler F R
J Cardiovasc Pharmacol. 1982;4 Suppl 3:S291-3.
The calcium channel blocker [3H]verapamil showed specific binding of high affinity (equilibrium dissociation constant, KD, of 4.25 nM) and low density (maximal number of binding sites, Bmax, 50 fmol/mg protein) in frog heart membranes. Nitrendipine, a new calcium channel blocker, had a potency comparable to verapamil in the inhibition of [3H]verapamil binding. Concentrations of Ca2+ in the medium exceeding 3 mM decreased [3H]verapamil binding. These findings are consistent with the concept that high-affinity binding sites for calcium channel blockers are associated with sarcolemmal calcium channels.
钙通道阻滞剂[3H]维拉帕米在蛙心膜中显示出高亲和力的特异性结合（平衡解离常数KD为4.25 nM）和低密度（最大结合位点数Bmax为50 fmol/mg蛋白质）。新型钙通道阻滞剂尼群地平在抑制[3H]维拉帕米结合方面具有与维拉帕米相当的效力。培养基中Ca2+浓度超过3 mM会降低[3H]维拉帕米的结合。这些发现与钙通道阻滞剂的高亲和力结合位点与肌膜钙通道相关的概念一致。
