禽类颗粒细胞中的离子电流。

Ionic currents in avian granulosa cells.

作者信息

Schwartz J L, Mealing G A, Asem E K, Whitfield J F, Tsang B K

机构信息

Division of Biological Sciences, National Research Council of Canada, Ottawa, Ontario.

出版信息

FEBS Lett. 1988 Dec 5;241(1-2):169-72. doi: 10.1016/0014-5793(88)81053-6.

DOI:10.1016/0014-5793(88)81053-6

PMID:2461875

Abstract

Transmembrane ionic currents have been recorded in single granulosa cells from the laying hen using the whole-cell patch-clamp technique. Under voltage-clamp conditions, depolarizing voltage steps evoked currents composed of a fast inactivating inward component and a delayed outward component. The former was activated at voltages more positive than -50 mV and was fully inactivated within 500 ms. It was blocked by D600 (methoxyverapamil) and by cobalt, suggesting that it is a calcium current. The latter displayed inward rectification and did not inactivate during long duration pulses. It was blocked by tetraethylammonium indicating that it is a potassium current. This is the first evidence of the existence of potassium and calcium transmembrane currents in granulosa cells.

摘要

采用全细胞膜片钳技术，在产蛋母鸡的单个颗粒细胞中记录到跨膜离子电流。在电压钳制条件下，去极化电压阶跃诱发的电流由快速失活的内向成分和延迟的外向成分组成。前者在电压高于 -50 mV 时被激活，并在 500 毫秒内完全失活。它被 D600（甲氧基维拉帕米）和钴阻断，表明它是一种钙电流。后者表现出内向整流，并且在长时间脉冲期间不会失活。它被四乙铵阻断，表明它是一种钾电流。这是颗粒细胞中存在钾和钙跨膜电流的首个证据。