不同种属动物对强心甙正性肌力作用的敏感性不同,可能是与对细胞膜强心甙受体亲和力以及抑制Na~+K~+-ATP酶的能力相关的。作者定量测定大鼠和豚鼠心脏中的[~3H]哇巴因结合部位以及Na~+K~+-ATP酶的特性。所得资料表明,在大鼠的心脏中有对药物亲和力高和亲和力低不同的结合部位。其离解常数分别为K_D=10~(-7)M,和K_D~’=3×10~(-5)M。但是药物的结合能力是不相同的,高亲和力受体对药物反而 Different species of animal on the positive role of cardiac glycosides positive different sensitivities may be related to the cell membrane cardiac glycoside receptor affinity and the ability to inhibit Na ~ + K ~ + -ATP enzyme. The authors quantified [~ 3H] ouabain binding sites and Na ~ + K ~ + -ATPase in rat and guinea pig hearts. The data obtained show that there are different binding sites in the rat’s heart that have different affinity and affinity to the drug. The dissociation constants are K_D = 10 ~ (-7) M and K_D ~ ’= 3 × 10 ~ (-5) M, respectively. However, the binding capacity of the drug is not the same, the high affinity receptor on the drug instead