Characterization and solubilization of the nitrendipine binding protein from canine small intestinal circular smooth muscle

The binding of nitrendipine, a calcium channel blocking agent, to the microsomes prepared from canine small intestinal circular smooth muscle was characterized. The binding of this 1,4-dihydropyridine to the membrane was reversible, saturable and of high affinity with a dissociation constant of 0.28 nM and a maximal binding of 91 fmol/mg microsomal protein. The binding occurred with an association rate constant of 0.094 nM-1 min-1 and …