Ouabain sensitivity of the Na+, K+-ATPase activity from single bovine cardiac Purkinje fiber and adjacent papillary muscle.
Ouabain sensitivity of the Na+, K+-ATPase activity from single bovine cardiac Purkinje fiber and adjacent papillary muscle.
复制标题
哇巴因对单个牛心脏浦肯野纤维和邻近乳头肌的 Na、K-ATP 酶活性的敏感性。
DOI：
10.1016/0022-2828(78)90359-0
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发表时间：
1978
影响因子：
5
通讯作者：
A. M. Watanabe
中科院分区：
文献类型：
--
作者：
F. Palfi;H. R. Besch;A. M. Watanabe
在电生理学评估时，浦肯野纤维对哇巴因毒性作用的敏感性大于心室肌纤维。我们试图在体外确定这是否反映了Na+，K+-ATPase活性的差异敏感性。Purkinje纤维和邻近的乳头肌被均质在一种介质中，该介质防止形成不透膜的囊泡，从而防止离子积累，并允许膜的两侧暴露于哇巴因、底物和辅因子。在此条件下，浦肯野纤维的Na+，K+-ATPase活性并不比邻近乳头肌的活性对哇巴因更敏感。结果表明，体内存在明显的哇巴因-Na+，K+-ATPase相互作用，除哇巴因对Na+，K+-ATPase的固有敏感性外，还可能存在其他因素。
When assessed electrophysiologically, the sensitivity of Purkinje fibers to the toxic effects of ouabain is greater than that of ventricular muscle fibers. We have attempted to determinein vitrowhether this is a reflection of a differential sensitivity of the Na+, K+-ATPase activity. Purkinje fibers and adjacent papillary muscle were homogenized in a medium which prevented the formation of impermeable membrane vesicles, thus preventing ion accumulation and allowing both sides of the membrane to be exposed to ouabaain, substrate, and cofactors. Under these conditions the Na+, K+-ATPase activity from Purkinje fibers was not more sensitive to ouabain compared to the activity from adjacent papillary muscle. The results suggest that factors other than inherent ouabain sensitivity of the Na+, K+-ATPase must underlie the apparent differential ouabain-Na+, K+-ATPase interactionin vivo.