Calmodulin‐ and protein phosphorylation‐independent release of catecholamines from PC‐12 cells

FEBS Letters

Miller, Richard J.¹  Matthies, Heinrich J.G.¹  Palfrey, H.Clive¹ 

[1] Department of Pharmacological and Physiological Sciences, The University of Chicago, Chicago, IL 60637, USA

关键词: Exocytosis;    Protein kinase C;    cAMP-dependent protein kinase;    Calmodulin;    (PC-12 cell);   

DOI  :  10.1016/0014-5793(88)81132-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Catecholamine secretion from PC-12 cells can be triggered by agents that increase intracellular Ca²⁺ and is enhanced by phorbol esters and agents that elevate intracellular cAMP concentrations. In mutant PC-12 cells lacking cAMP-dependent protein kinase (PK-A) in which protein kinase C (PK-C) was down-regulated, Ca²⁺-dependent secretion occurred normally but was no longer enhanced by cAMP or phorbol esters. In digitonin-permeabilized PC-12 cells that lacked PK-C and PK-A, a range of calmodulin (CaM) inhibitors failed to block Ca²⁺-triggered catecholamine release. Moreover, Mn²⁺, a CaM activator, failed to trigger catecholamine release whereas Ba²⁺, which does not activate CaM, supported secretion. These results indicate that the basic mechanism of stimulus/secretion coupling in PC-12 cells does not absolutely require a regulated protein phosphorylation- or calmodulin-dependent step.

【 授权许可】

Unknown