Cell Swelling-induced Peptide Hormone Secretion

Cellular Physiology and Biochemistry

Vladimír Štrbák¹ 

关键词: Cell Volume;    Exocytosis;    Ca2+ independent hormone secretion;    Signaling;    Resistance to physiological inhibitor;    Specificity;    Ischemic preconditioning;    SIADH;   

DOI  :  10.1159/000335849

学科分类：分子生物学，细胞生物学和基因

来源: S Karger AG

【 摘 要 】

Cell swelling induces peptide exocytosis using unique signaling pathway. Hyposmotic-induced secretion in normal cells is not mediated by specific receptors, is independent from extra and intracellular Ca²⁺, sodium and potassium channels activity, prostaglandins, leukotriens, does not involve cytoskeleton, cAMP generation, phospholipase A₂, G proteins, protein kinase C. It is promoted by swelling of the secretory vesicles. Resistance to endogenous inhibitors is frequent attribute of this type of secretion. Swelling-induced secretion involves also secretory vesicles not involved in conventional stimulation. Hyposmosis-induced insulin secretion is more sensitive to high cellular cholesterol than conventional one suggesting substantial difference between mechanisms. Participation of sequential exocytosis as dominating mechanism in swelling-induced exocytosis is hypothesized. Signaling and response in tumor cells often differs from native cells and varies markedly between cell lines. Pathogenetic implications cell swelling could be involved in alcohol induced hypoglycemia in diabetic patients and release of peptides from pituitary and neurons. Swelling-induced products could be mediators of ischemic preconditioning involved also in protection of diabetic heart. Swelling-induced exocytosis is an ancient mechanism generally present in cells; in cells engaged in water and salt regulation is covered by specific response mediated by specific signaling. Disturbance of specific response leads to swelling-induced - inappropriate secretion of antidiuretic hormone - SIADH.

【 授权许可】

CC BY-NC-ND