Studies on the mechanism of inhibition of hepatic cAMP accumulation by vasopressin

FEBS Letters

Exton, John H.¹  Shipp, Clanton C.¹  Morgan, Noel G.¹ 

[1] Laboratories for the Studies of Metabolic Disorders, Howard Hughes Medical Institute, Nashville, TN 37232, USA

关键词: Hepatocyte;    cAMP;    Vasopressin;    Calcium;    Adenylate cyclase;    Glucagon;   

DOI  :  10.1016/0014-5793(83)80835-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Vasopressin elicited a dose-dependent inhibition of glucagon-induced cAMP accumulation in isolated hepatocytes. This response was not diminished by incubation of cells with the calmodulin antagonists trifluoperazine or chlorpromazine and was only slightly reduced in Ca²⁺-depleted hepatocytes. Half-maximal inhibition of cAMP accumulation occurred at 8 × 10^-11 M vasopressin, a dose which does not increase cytosolic Ca²⁺ in hepatocytes. Direct activation of adenylate cyclase by forskolin was significantly inhibited by vasopressin in Ca²⁺-depleted cells. It is concluded that inhibition of hormone-induced cAMP accumulation by vasopressin in liver is not dependent on cellular Ca²⁺ mobilisation but may involve direct inhibition of adenylate cyclase.

【 授权许可】

Unknown