MOLECULAR MECHANISMS OF SOMATOSTATINS INHIBITION OF HORMONE-RELEASE - PARTICIPATION OF VOLTAGE-GATED CALCIUM CHANNELS AND G-PROTEINS

被引：0
作者：
SCHERUBL, H [1 ]
HESCHELER, J [1 ]
RIECKEN, EO [1 ]
机构：
[1] FREE UNIV BERLIN,DEPT PHARMACOL,W-1000 BERLIN 33,GERMANY
来源：
HORMONE AND METABOLIC RESEARCH | 1993年 / 27卷
关键词：
SOMATOSTATIN; CALCIUM CHANNELS; G-PROTEINS; NEUROENDOCRINE CELLS; CARCINOID;
D O I：
暂无
中图分类号：
R5 [内科学];
学科分类号：
1002 ; 100201 ;
摘要：
Somatostatin is known to inhibit hormone release from various neuroendocrine cells. In order to understand the mechanisms underlying somatostatin's action we performed patch-clamp experiments in GH3 pituitary, rMTC 44-2 thyroid and BON carcinoid cells. Calcium-mediated hormone release depended on the intracellular calcium concentration and thus on the calcium influx through voltage-gated calcium channels. In addition to inhibiting the cAMP-dependent secretory pathway, somatostatin reduced the calcium inward currents and thereby hormone release. The inhibition of voltage-gated calcium channels by somatostatin was mediated by ''signal transducing'' Go proteins. Thus, somatostatin's actions on hormone release involve both cAMP and intracellular calcium as second messengers. Patch-clamp experiments of voltage-gated calcium channels allow functional studies on the coupling of somatostatin receptors to cellular effector systems.
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页码：1 / 4
页数：4
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