A subtype of opioid κ‐receptor is coupled to inhibition of Gil‐mediated phospholipase C activity in the guinea pig cerebellum

FEBS Letters

Satoh, Masamichi⁴  Ueda, Hiroshi¹  Ui, Michio²  Katada, Toshiaki⁵  Misawa, Hidemi³ 

[1] Department of Pharmacology, Yokohama City University School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236, Japan;RIKEN, Wako 351-01, Japan;Tokyo Metropolitan Institute for Neuroscience, Tokyo 183, Japan;Department of Molecular Pharmacology, Faculty of Pharmaceutical Sciences, Kyoto University, Kyoto 606-01, Japan;Department of Physiological Chemistry, Faculty of Pharmaceutical Science, The University of Tokyo, Tokyo 113, Japan

关键词: Opioid κ-receptor;    Gi1-type G-protein;    Phospholipase C;    G-protein;    heterotrimeric GTP-binding proteins;    PLC;    phospholipase C;    PTX;    pertussis toxin;    InsP3;    inositol 1;    4;    5-trisphosphate;    PIP2;    phosphatidylinositol 4;    5-bisphosphate;   

DOI  :  10.1016/0014-5793(95)00162-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

PLC activity was stimulated either by 1–100 μM of GTP or by 100–3,000 μM Ca²⁺ in lysed synaptosomal membranes of the guinea pig cerebellum. The κ-opioid receptor agonist selectively inhibited the PLC activity stimulated by 100 μM GTP, but not by 100–3,000 μM Ca²⁺. Pretreatment of membranes with PTX abolished such a κ-agonist-induced inhibition of PLC activity. The reconstitution of Gi1, but not of Go purified from porcine brains with PTX-treated membranes showed a complete recovery of the κ-agonist-inhibition of PLC activity. These findings suggest that a novel subtype κ-receptor mediates inhibition of PLC through inhibiting the intrinsic activity of PTX-substrate G-proteins.

【 授权许可】

Unknown