Ramirez V D, Gallardo E, Hartter D
J Endocrinol Invest. 1980 Jan-Mar;3(1):29-37. doi: 10.1007/BF03348214.
This paper deals with the effect of temperature (t degrees), ions, prostaglandin (PGE2) and testosterone on the rate of release of LHRH from the superfused medial basal hypothalamus (MBH) of normal or castrated male rats in an effort to further validate the biological properties of this preparation. LHRH in the perfusate is nondetectable when the MBH is at 0 C, warming to 37 C produces a sharp rise in LHRH and then stabilization at a level at least threefold the one calculated for the 0 C experiment. Basal release rate of LHRH is t degrees and calcium dependent, as is the stimulatory action of potassium. Infusion of high K+ induces approximately a fivefold increase in the release rate of LHRH and stays at this high level for as long as the infusion lasts (50 min). LHRH stimulation by PGE2 (pulse) proceeds in the absence of external calcium, and the effect lasts longer than the potassium (pulse) action. Surprisingly, MBHs from long-ter castrated males (60-90 days) release less LHRH per minute than intact male MBHs during the steady state phase of LHRH secretion; testosterone propionate (TP, 200 microgram/100 g BW x 3 days) increases significantly the rate of release in castrate rats and is not related to the amount of LHRH assayed in the MBH. MBHs of untreated castrated rats or castrated rats treated with TP, show a reduced LHRH secretion in response to PGE2. It is concluded that this preparation can be used at advantage to study the rate of LHRH release in a variety of experimental paradigms.
本文研究了温度（t摄氏度）、离子、前列腺素（PGE2）和睾酮对正常或去势雄性大鼠超灌流内侧基底部下丘脑（MBH）释放促黄体生成素释放激素（LHRH）速率的影响，以进一步验证该制剂的生物学特性。当MBH处于0℃时，灌流液中检测不到LHRH，升温至37℃会使LHRH急剧上升，然后稳定在至少是0℃实验计算水平三倍的水平。LHRH的基础释放速率依赖于温度和钙离子，钾离子的刺激作用也是如此。输注高钾会使LHRH释放速率增加约五倍，并在输注持续期间（50分钟）一直保持在这个高水平。PGE2（脉冲）对LHRH的刺激在无细胞外钙的情况下进行，且其作用持续时间比钾离子（脉冲）的作用更长。令人惊讶的是，在LHRH分泌的稳态阶段，长期去势雄性大鼠（60 - 90天）的MBH每分钟释放的LHRH比完整雄性大鼠的MBH少；丙酸睾酮（TP，200微克/100克体重×3天）可显著提高去势大鼠的释放速率，且与MBH中检测到的LHRH量无关。未经处理的去势大鼠或用TP处理的去势大鼠的MBH对PGE2的反应显示LHRH分泌减少。结论是，该制剂可用于多种实验范式，以研究LHRH的释放速率。
