Murao S, Sato M, Tamaki M, Niimi M, Ishida T, Takahara J
First Department of Internal Medicine, Kagawa Medical School, Japan.
Res Commun Mol Pathol Pharmacol. 1995 Sep;89(3):269-77.
The secretion of growth hormone (GH) shows a pulsatile pattern in many mammalian species, and depends on the interaction of two hypothalamic hormones, GH-releasing hormone (GHRH) and somatostatin (SRIH). A surge of GHRH secretion into the hypophysial portal blood induces peak secretion of GH from the anterior pituitary. To study whether the rhythmic and reciprocal oscillation in secretion of GHRH and SRIH are associated with changes in synthesis of these peptides, we examined the expression of hypothalamic GHRH and SRIH mRNA by Northern blotting during trough and peak phases of GH secretion in male mice. Hypothalamic GHRH and SRIH mRNA levels did not differ between trough and peak phases of GH secretion. This result suggests that changes in GHRH and SRIH secretion have little association with changes in the synthesis of these peptides at the hypothalamus in the male mouse.
在许多哺乳动物物种中，生长激素（GH）的分泌呈现出脉冲式模式，并且依赖于两种下丘脑激素——生长激素释放激素（GHRH）和生长抑素（SRIH）的相互作用。GHRH分泌进入垂体门脉血的激增会诱导垂体前叶GH的峰值分泌。为了研究GHRH和SRIH分泌的节律性和相互振荡是否与这些肽的合成变化相关，我们在雄性小鼠GH分泌的低谷期和高峰期通过Northern印迹法检测了下丘脑GHRH和SRIH mRNA的表达。在GH分泌的低谷期和高峰期之间，下丘脑GHRH和SRIH mRNA水平没有差异。这一结果表明，在雄性小鼠中，GHRH和SRIH分泌的变化与下丘脑这些肽的合成变化几乎没有关联。
