Somatostatin release from the median eminence of unanesthetized rats: lack of correlation with pharmacologically suppressed growth hormone secretion.
Somatostatin release from the median eminence of unanesthetized rats: lack of correlation with pharmacologically suppressed growth hormone secretion.
复制标题
未麻醉大鼠中位隆起的生长抑素释放：与药物抑制生长激素分泌缺乏相关性。
DOI：
10.1159/000124074
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发表时间：
1985
影响因子：
4.1
通讯作者：
Martin,JB
中科院分区：
文献类型：
--
作者：
Fukata,J;Kasting,NW;Martin,JB
我们描述了一种推拉灌流技术来研究生长抑素在药物抑制生长激素(GH)分泌中的作用。在慢性插管非麻醉雄性大鼠上研究了正中隆起(ME)释放的免疫反应性生长抑素(IRS)。对照组大鼠血浆GH水平呈正常超常节律，灌流液中IRS水平相对稳定(约30pg/15min)。侧脑室注射人生长激素(40微克)、神经降压素(2微克)、胰高血糖素(25微克)或静脉注射。注射α肾上腺素能激动剂羟甲唑啉(50微克/千克体重)或内毒素(150微克/千克体重体重)。抑制了随后的生长激素激增。然而，在这些大鼠中，ME灌流液中的IRS水平与对照组相比没有显著变化。这些结果表明，生长抑素释放的变化可能在这些物质引起的血浆GH水平抑制中起次要作用，而主要的调节作用可能是通过抑制生长激素释放因子来实现的。
We describe a push-pull perfusion technique to investigate the role of somatostatin in the pharmacological suppression of growth hormone (GH) secretion. Immunoreactive somatostatin (IRS) released from the median eminence (ME) was studied in chronically cannulated, unanesthetized male rats. In control rats which received vehicle injection, plasma GH levels showed a normal ultradian rhythm and relatively stable levels of IRS (around 30 pg/15 min) appeared in the perfusate during the 6-h perfusion. Intracerebroventricular (i.c.v) administration of human growth hormone (40 µg), neurotensin (2 µg), glucagon (25 µg) or intravenous (i.v.) injection of oxymetazoline (50 µg/kg b.w.), an α-adrenergic agonist, or endotoxin (150 µg/kg b.w.) suppressed subsequent GH surges. In these rats, however, IRS levels in the ME perfusate failed to change significantly compared to control rats. These results suggest that changes in somatostatin release may play a minor role in the suppression of plasma GH levels caused by these substances, and that major regulatory effects may be achieved via the suppression of growth hormone-releasing factor release.