Human chorionic gonadotropin activates the inositol 1,4,5‐trisphosphate‐Ca2+ intracellular signalling system in bovine luteal cells

[摘要]

Human chorionic gonadotropin, hCG, a hormone which increases intracellular cAMP, provoked rapid (30 s) and sustained (up to 30 min) increases in the levels of inositol mono-, bis- and trisphosphates (IP, IP₂ and IP₃, respectively) in bovine luteal cells. LiCl (10 mM) enhanced inositol phosphate accumulation in response to hCG. Concentration-dependent increases in inositol phosphates, cAMP and progesterone accumulation were observed in hCG-treated luteal cells. hCG also induced rapid and concentration-dependent increases in cytosolic free Ca²⁺ as measured by quin 2 fluorescence. These findings demonstrate that hCG stimulates the phospholipase C-IP₃ and diacylglycerol ‘second messenger’ system in the bovine corpus luteum.

[学科分类] 生物化学/生物物理

[关键词] Ca2+Gonadotropin Inositol phospholipid Inositol phosphate (Corpus luteum);hCG;human chorionic gonadotropin;[Ca2+]i;cytosolic free calcium concentration;quin 2/AM;quin 2 tetraacetoxymethyl ester;IP3;inositol trisphosphate;IP2;inositol bisphosphate;IP;inositol phosphate;PI;phosphatidylinositol;PIP;phosphatidylinositol 4-phosphate;PlP2;phosphatidylinositol 4;5-biphosphate;DAG;1;2-diacylglycerol