三磷酸腺苷（ATP）对透析过的藤壶肌纤维中钙外流的影响。

The effect of ATP on calcium efflux in dialyzed barnacle muscle fibres.

作者信息

DiPolo R, Caputo C

出版信息

Biochim Biophys Acta. 1977 Nov 1;470(3):389-94. doi: 10.1016/0005-2736(77)90130-4.

Abstract

Calcium efflux has been studied in barnacle muscle fibres under internal dialysis conditions. Prolonged dialysis of these fibres, with a medium free of ATP and containing 2 mM cyanide and 1 mM iodoacetate, causes the ATP in the perfusion effluent to fall to less than 20 micrometer. The mean calcium efflux from fibres dialyzed with EGTA buffered solution containing 0.3 micrometer ionized Ca and and no ATP is 0.6 pmol-cm-2-s-1. A two-fold stimulation of the calcium efflux is observed when ATP is added to fibres previously dialyzed with an ATP-free medium. Withdrawal of Na+ and Ca2+ from the external medium causes a marked drop in the Ca2+ efflux in the presence of internal ATP.

摘要

在内部透析条件下，对藤壶肌纤维中的钙外流进行了研究。用不含ATP且含有2 mM氰化物和1 mM碘乙酸盐的介质对这些纤维进行长时间透析，会使灌注流出液中的ATP降至低于20微摩尔。用含有0.3微摩尔游离钙离子且不含ATP的EGTA缓冲溶液透析的纤维，其平均钙外流为0.6皮摩尔·厘米⁻²·秒⁻¹。当向先前用无ATP介质透析的纤维中添加ATP时，观察到钙外流增加了两倍。在存在内部ATP的情况下，从外部介质中去除Na⁺和Ca²⁺会导致Ca²⁺外流显著下降。