Evidence for a function of calcium influx in the stimulation of hormone release fron the parathyroid gland in the goat.
Evidence for a function of calcium influx in the stimulation of hormone release fron the parathyroid gland in the goat.
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钙流入刺激山羊甲状旁腺激素释放功能的证据。
DOI：
10.1111/j.1748-1716.1981.tb06858.x
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发表时间：
1981
期刊：
影响因子：
--
通讯作者：
O. Sand
中科院分区：
文献类型：
--
作者：
K. Hove;O. Sand
采用局部注射法研究了不同药物对山羊甲状旁腺激素（PTH）释放的急性影响。Ca ~（2+）或Sr ~（2+）可降低PTH的分泌速率，而EDTA引起的低钙血症可增加PTH的分泌。电压敏感性Ca ~（2+）通道阻滞剂（维拉帕米、D-600和硝苯地平）降低了PTH的分泌速率，而电压敏感性K ~+通道阻滞剂4-氨基吡啶的输注增加了PTH的释放。这些效应不是由于β-肾上腺素能紧张性改变，因为在持续输注β-受体阻滞剂普萘洛尔期间给药时，这些效应持续存在。我们认为，甲状旁腺细胞具有电压敏感的K+和Ca ~（2+）通道，和其他分泌细胞一样，储存的PTH的胞吐依赖于细胞外Ca ~（2+）的流入。为了解释血浆Ca ~（2+）水平与PTH释放之间的反比关系，我们假设血浆Ca ~（2+）对甲状旁腺细胞膜对Ca ~（2+）的通透性具有抑制作用。
The acute effects of various drugs on the release of parathyroid hormone (PTH) in goats were studied by local infusions in vivo. Infusions of Ca2+ or Sr2+ reduced the PTH secretion rate, whereas hypocalcemia induced by EDTA increased the PTH release. Blockers of voltage sensitive Ca2+ channels (verapamil, D-600 and nifedipine) lowered the PTH secretion rate, while infusion of 4-aminopyridine, which is a blocker of voltage sensitive K+ channels, increased the PTH release. These effects were not due to altered beta-adrenergic tonus, since the effects persisted when the drugs were administered during continuous infusion of the beta-blocker propranolol. We suggest that the parathyroid cells possess voltage sensitive K+ and Ca2+ channels, and that exocytosis of stored PTH depends on the influx of extracellular Ca2+ as in other secretory cells. In order to explain the inverse relationship between the plasma Ca2+ level and the PTH release, we postulate a suppressive effect of the plasma Ca2+ on the membrane permeability to Ca2+ in parathyroid cells.