Hemispheric asymmetry of rapid chloride responses to inositol trisphosphate and calcium in Xenopus oocytes

FEBS Letters

Lupu-Meiri, Monica¹  Shapira, Hagit¹  Oron, Yoram¹ 

[1] Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv 69978, Israel

关键词: Inositol trisphosphate;    Ca2+;    Oocyte;    Cl− channel;    (Xenopus);   

DOI  :  10.1016/0014-5793(88)80344-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Shallow injection of inositol 1,4,5-trisphosphate (IP₃) near the animal pole of the Xenopus oocyte resulted in a large depolarizing current that decayed rapidly. A similar injection near the vegetal pole produced a much smaller response characterized by a significantly slower rate of decay. Injection of CaCl₂ near the animal pole of the oocyte resulted in a large depolarizing current characterized by rapid rise and decay times. Injection near the vegetal pole of the cell produced responses that exhibited similar amplitudes but much longer rise and decay times. The protein kinase C (PK-C) activator, β-phorbol 12-myristate 13-acetate (PMA), significantly enhanced the rapid responses to IP₃ injections at either hemisphere but did not affect the amplitudes of the responses to CaCl₂. The PK-C inhibitor 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H-7) had no effect on the responses to CaCl₂. These results imply an asymmetric distribution of calcium stores and chloride channels between the two hemispheres of the oocyte.

【 授权许可】

Unknown