Ramaraj P, Subbarayan V S, Rao J A
Department of Biochemistry, Indian Institute of Science, Bangalore.
Indian J Biochem Biophys. 1991 Oct-Dec;28(5-6):536-40.
Sodium dodecyl sulphate-polyacrylamide gel electrophoresis of Percoll purified Leydig cell proteins from 20- and 120-day-old rats revealed a significant decrease in a low molecular weight peptide in the adult rats. Administration of human chorionic gonadotropin to immature rats resulted in a decrease in the low molecular weight peptide along with increase in testosterone production. Modulation of the peptide by human chorionic gonadotropin could be confirmed by Western blotting. The presence of a similar peptide could be detected by Western blotting in testes of immature mouse, hamster, guinea pig but not in adrenal, placenta and corpus luteum. Administration of testosterone propionate which is known to inhibit the pituitary luteinizing hormone levels in adult rats resulted in an increase in the low molecular weight peptide, as checked by Western blotting. It is suggested that this peptide may have a role in regulation of acquisition of responsiveness to luteinizing hormone by immature rat Leydig cells.
对20日龄和120日龄大鼠经Percoll纯化的睾丸间质细胞蛋白质进行十二烷基硫酸钠-聚丙烯酰胺凝胶电泳分析，结果显示成年大鼠中一种低分子量肽显著减少。对未成熟大鼠注射人绒毛膜促性腺激素，导致低分子量肽减少，同时睾酮分泌增加。通过蛋白质免疫印迹法可证实人绒毛膜促性腺激素对该肽的调节作用。通过蛋白质免疫印迹法可在未成熟小鼠、仓鼠、豚鼠的睾丸中检测到类似肽，但在肾上腺、胎盘和黄体中未检测到。已知丙酸睾酮可抑制成年大鼠垂体促黄体生成素水平，经蛋白质免疫印迹法检测，注射丙酸睾酮后低分子量肽增加。提示该肽可能在调节未成熟大鼠睾丸间质细胞对促黄体生成素反应性的获得中起作用。
