CA2+ RELEASE OF LHRH FROM CULTURED LHRH NEURONS FROM EMBRYONIC OLFACTORY PLACODE

CA2 从胚胎嗅觉板培养的 LHRH 神经元中释放 LHRH

• 批准号: 6277676
• 负责人: Ei Terasawa-Grilley
• 金额: $ 6.06万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-05-01 至 1999-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6277676
• 关键词: Primates; animal tissue; clinical research; endocrine gland /system; growth /development; microscopy; mother /infant health care; nervous system; women's health

OBJECTIVE: To determine the role of Ca2+ in LHRH release in vitro. RESULTS In a previous study we have reported that cultured LHRH neurons derived from the olfactory placode of monkey embryos release LHRH into media in a pulsatile manner at approximately 50-min intervals. As a first step in studying the mechanism of LHRH pulse generation, we examined the role of calcium in LHRH release using cultured LHRH neurons. The results are summarized as follows 1) Exposing the cells to a low Ca2+ (10 nM) buffer solution suppressed LHRH release; 2) LHRH release from cultured LHRH cells was stimulated by the L-type Ca2+ channel stimulant, Bay K 8644 (1 M), while it was suppressed by the L-type Ca2+ channel blocker, nifedipine (1 M), but not by the N-type channel blocker, w-conotoxin (1 M); 3) The intracellular Ca2+ ([Ca2+]i) transporting ATPase antagonist, thapsigargin (10 M), suppressed LHRH release, while the intracellular Ca2+ stimulant, ryanodine (1 M) stimulated LHRH release; 4) Carbonyl-cyanide-P-trifluoromethoxyphenyl hydrazone (FCCP, 1 mM), a mitochondrial Ca2+ mobilizer, tended to stimulate LHRH release. These results indicate that 1) release of LHRH is influenced by the presence of extracellular Ca2+ ([Ca2+]e), 2) Ca2+ enters the cell via L-type channels, but not N-type channels, and 3) mobilization of [Ca2+]i is important for LHRH release. It is concluded that the presence of [Ca2+]e and Ca2+ entry into the cell are essential for pulsatile LHRH release in cultured LHRH neurons. Moreover, mobilization of [Ca2+]i appears to contribute to LHRH release in cells. FUTURE DIRECTIONS We will examine if LHRH release is correlated to [Ca2+]i oscillations. KEY WORDS LHRH neurons, pulsatility, monkey embryos, LHRH release in vitro, intracellular Ca2+

目的：探讨钙离子在LHRH释放中的作用。 体外 结果在以前的研究中，我们已经报道了培养的 猴胚胎嗅板LHRH神经元的培养 在约50分钟时以脉冲方式将LHRH释放到培养基中 的间隔 作为研究LHRH脉冲机制的第一步， 第二代，我们研究了钙在LHRH释放中的作用， 培养的LHRH神经元。 结果总结如下：1） 将细胞暴露于低Ca 2+（10 nM）缓冲溶液抑制 LHRH释放：2）刺激培养的LHRH细胞释放LHRH L-型钙通道刺激剂Bay K 8644（1 M），而 L-型钙通道阻滞剂硝苯地平（1 M）抑制，但 而不被N-型通道阻断剂w-芋螺毒素（1 M）所抑制; 3） 胞内Ca 2+（[Ca 2 +]i）转运ATP酶拮抗剂， 毒胡萝卜素（10 M），抑制LHRH的释放，而细胞内 钙离子刺激剂ryanodine（1 M）刺激的LHRH释放; 4） 羰基-氰化物-对三氟甲氧基苯腙（FCCP，1 mM），a 线粒体Ca ~（2+）动员剂，倾向于刺激LHRH释放。 这些 结果表明：（1）LHRH的释放受 细胞外Ca ~（2+）（[Ca ~（2+）]e），2）Ca ~（2+）通过L-型钙通道进入细胞 通道，但不是N型通道，和3）动员[Ca 2 +]i是 对LHRH释放很重要。 它的结论是， [Ca2[+]e和Ca ~（2+）进入细胞是LHRH搏动的必要条件 在培养的LHRH神经元中释放。 此外，[Ca 2 +]i的动员 似乎有助于细胞中LHRH的释放。 未来发展方向 将检查LHRH释放是否与[Ca 2 +]i振荡相关。 关键词LHRH神经元，搏动性，猴胚胎，LHRH释放 体外，细胞内Ca 2 +