中药对大鼠下丘脑生长抑素及垂体生长激素基因表达与蛋白表达的调节作用

Regulative Effect of Chinese Herbal Medicine on Gene and Protein Expression Levels of Somatostatin and Growth Hormone in Hypothalamus and Hypophysis

目的:观察滋阴泻火及益肾填精中药对大鼠下丘脑生长激素释放激素(GHRH)、生长抑素(SS)、垂体生长激素(GH)的基因表达及蛋白表达水平的影响。方法:将青春期SD雌性大白鼠分为3组,即对照组(喂饲生理盐水)、滋阴泻火组(喂饲滋阴泻火中药合剂)及益肾填精组(喂饲益肾填精中药合剂)。采用原位杂交、免疫组化技术分别检测下丘脑室周核SS mRNA及SS表达水平,弓状核GHRH mRNA及垂体GH的表达水平。结果:滋阴泻火组大鼠的下丘脑室周核SS基因表达、蛋白表达明显上调(P<0.05),垂体GH蛋白表达明显下调(P<0.05);而益肾填精组大鼠则相反,其室周核SS基因表达、蛋白表达明显下调(P<0.05),垂体GH蛋白表达明显上调(P<0.05)。但两组下丘脑弓状核GHRH基因表达无明显变化。结论:滋阴泻火和益肾填精中药可转录水平及蛋白合成水平,调节下丘脑室凋核SS的基因表达及蛋白表达,从而调节垂体GH的合成及翻译,但对弓状核GHRH的基因表达无明显影响。

Objective: To observe the effect of Chinese herbal medicine for nourishing-Yin to purge-Fire (NYPF) and reinforcing-Shen to supplement essence (RSSE) on hypothalamus growth hormone releasing hormone (GHRH) and somatostatin (SS), and hypophysis growth hormone (GH) gene and protein expressions. Methods: Puber-tal female SD rats were randomly divided into three groups, the control group (fed with normal saline), the tested group A and B (fed with NYPF and RSSE respectively). SS mRNA expression and protein level in the periventricular nucleus, GHRH mRNA expression in the arcuate nucleus of hypothalamus and GH protein level in hypophysis were measured by immunohistochemistry, in situ hybridization and computer image processing. Results: The SS mRNA expression and SS protein level were up-regulated (P<0.05) and GH protein level down-regulated (P<0.05) in the tested group A, while in the tested group B, the SS mRNA expression and SS protein level were down-regulated ( P < 0.05) and GH protein level up-regulated ( P < 0.05). But the GHRH mRNA expression between the two tested groups were not significantly different. Conclusion: Chinese herbal medicine of NYPF and RKSE could regulate the SS mRNA expression and SS protein level in the periventricular nucleus of hypothalamus at the transcription level, thereby could regulate the synthesis and release of GH in hypophysis. But they could not affect the GHRH mRNA expression in arcuate nucleus of hypothalamus.