Islet‐activating protein prevents nicotinic acid‐induced GTPase stimulation and GTP but not GTPγS‐induced adenylate cyclase inhibition in rat adipocytes

FEBS Letters

Jakobs, Karl H.¹  Schultz, Günter¹  Aktories, Klaus¹ 

[1] Pharmakologisches Institut der Universität Heidelberg, Im Neuenheimer Feld 366, D-6900 Heidelberg, FRG

关键词: Islet-activating protein;    Bordetella pertussis toxin;    Rat adipocyte;    Adenylate cyclase;    GTPase;    Nicotinic acid;   

DOI  :  10.1016/0014-5793(83)80254-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The influence of islet-activating protein (IAP), a Bordetella pertussis toxin, was studied on adenylate cyclase and GTPase activities in rat adipocyte membranes. Pretreatment of rats or intact rat adipocytes with IAP did not affect adenylate cyclase inhibition by the stable GTP analog, GTPγS, whereas inhibition by GTP was abolished. Concomitantly, activation of the adipocyte enzyme by sodium and its inhibition by nicotinic acid were prevented. Furthermore, IAP treatment of adipocyte membranes prevented nicotinic acid-induced stimulation of a high affinity GTPase. The data suggest that a GTP-hydrolyzing system involved in the inhibitory regulation of adenylate cyclase is the target of IAP's action.

【 授权许可】

Unknown