在细胞外钙缺乏的情况下，钾会刺激甲状旁腺激素的释放。

Potassium stimulates parathyroid hormone release in the absence of extracellular calcium.

作者信息

Olles P, Tschopp F, Dempster D W, Tobler P H, Muff R, Fischer J A

出版信息

Mol Cell Endocrinol. 1983 Sep;32(1):1-12. doi: 10.1016/0303-7207(83)90094-1.

Abstract

Potassium-stimulated release of many hormones requires the presence of extracellular calcium. At variance with this mechanism, potassium-evoked parathyroid hormone (PTH) release from perifused dispersed bovine parathyroid cells also occurred in calcium-free medium containing 1 mM EGTA. Tetraethylammonium, which presumably suppresses the efflux of potassium from parathyroid cells, also stimulated PTH secretion. Removal of sodium did not suppress potassium-stimulated PTH secretion, but inhibited the release of the hormone evoked by calcium removal and by isoproterenol. Ouabain, on the other hand, suppressed the release of PTH evoked by calcium removal and by potassium, but not by isoproterenol. Unlike high potassium and removal of calcium, isoproterenol caused a parallel increase in cAMP release. In conclusion, PTH secretion is reversibly stimulated by potassium in the absence of extracellular calcium. Our findings suggest that potassium stimulates PTH secretion by a unique mechanism the nature of which remains to be elucidated.

摘要

许多激素的钾刺激释放需要细胞外钙的存在。与这种机制不同的是，在含有1 mM乙二醇双（2-氨基乙基醚）四乙酸（EGTA）的无钙培养基中，钾诱导的灌注分散牛甲状旁腺细胞释放甲状旁腺激素（PTH）也会发生。四乙铵可能会抑制钾从甲状旁腺细胞外流，但它也会刺激PTH分泌。去除钠不会抑制钾刺激的PTH分泌，但会抑制因去除钙和异丙肾上腺素引起的激素释放。另一方面，哇巴因抑制因去除钙和钾引起的PTH释放，但不抑制异丙肾上腺素引起的释放。与高钾和去除钙不同，异丙肾上腺素会导致环磷酸腺苷（cAMP）释放平行增加。总之，在没有细胞外钙的情况下，钾会可逆地刺激PTH分泌。我们的研究结果表明，钾通过一种独特的机制刺激PTH分泌，其本质尚待阐明。