| 摘要: |
| 作者于1990年9月 - 1991年1月采用离体灌流培育方法对鲤鱼脑垂体促性腺激素的分泌调节进行研究。结果表明，脑垂体基础促性腺激素（GtH）分泌不依赖于细胞外钙离子（Ca2+）；但脉冲式鲑鱼促性腺激素释放激素（sGnRH）刺激的GtH分泌，则依赖于细胞外Ca2+，且细胞外Ca2+的作用至少部分通过电位敏感性Ca2+通道。50 mmol/L高浓度钾离子（K+）显著刺激脑垂体基础GtH分泌，K+的作用是依赖于时间和细胞外Ca2+的；高浓度K+对脉冲式sGnRH刺激的GtH分泌没有显著影响。 |
| 关键词: 鲑鱼 GnRH 促性腺激素 钙离子 钾离子 灌流 鲤鱼 |
| DOI： |
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| 基金项目:高等学校博士点科学基金资助;加拿大国际发展研究中心资助，3－p－83－1101号 |
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| EFFECTS OF EXTRACELLULAR CALCIUM AND POTASSIUM ON THE`. REGULATION OF GONADOTROPIN SECRETION FROM FITUITARY OF COMMON CARP IN VITRO |
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Lin Xinwei, Li Yingwen, Lin Haoran
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Depariment of Biology. Zhongshan University. Guangzhou 510275
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| Abstract: |
| The effects of extracellular Ca2+ and K+ on the basal and salmon GnRH (sGnRH)-stimulated gonadotropin (GtH) release from pituitary of the common carp (Cyprinus carpia) were studied by using an in vitro perifusion system for pituitary fragments. The basal GtH release from the common carp’s perifused pituitary extracellular Ca2+-independent. The GtH release from the common carp’s perifused pituitary in response to 2 min pulses of sGnRH (1, 10, 100 n mol/L) was extracellular Ca2+-dependent; in the absence of extracellular Ca2+ or the reduction in Ca2+ concentration, the significant decreases in the GtH release responses to sGnRH were observed. Voltagesensitive calcium channels (VSCC) and antagonist verapamil (VER) dosedependently and significantly inhibited GtH release responses to 2 min pulses of sGnRH, in a VER was ineffective on the basal GtH secretion. These results indicate that the effect of extracellular Ca2+ on the GtH-releasing action of sGnRH is, at least, partially through the action of VSCC. 50 m mol/L K+ significantly stimulated the basal GtH release from the perifused pituitary of the common carp, and the action of K+ was time and extracellular Ca2+-dependent. Moreover, no significant influence of increased concentration of K+ on sGnRH-induced GtH release was observed. |
| Key words: Salmon, GnRH, Gonadotropin, Calcium, Potassium, Perifusion, Common carp |
