Xiao Ai-Jiao, Wang Jing-Lei, Fang Lian, Kuang Hai-Bin
Department of Physiology, Jiangxi Medical College, Nanchang 330006, China.
Sheng Li Xue Bao. 2004 Jun 25;56(3):353-6.
The present study was carried out to investigate the effect of antisense c-myb oligodeoxynucleotides (ODN) on hCG-induced testosterone secretion in isolated rat Leydig cells. The effects of cAMP, Ca(2+) and cycloheximide (CYX) on c-Myb protein expression and testosterone secretion were also observed. The results showed that antisense c-myb ODN inhibited hCG-induced testosterone secretion of isolated rat Leydig cells in a dose-dependent manner. At the same time, integral optical density immunostaining of Myb in Leydig cells was also remarkably reduced. Nonsense tat ODN had no effect on Leydig cells. Further experiments showed that dbcAMP (100 micromol/L) obviously increased hCG-induced testosterone secretion and integral optical density (IOD) immunostaining of Myb in Leydig cells. Verapamil (10 micromol/L), a Ca(2+) channel blocker, and cycloheximide (50 microg/ml), a protein synthesis inhibitor, reduced the immunostaining of c-Myb, and also lowered hCG-induced testosterone secretion in isolated rat Leydig cells. The results indicate that c-myb closely correlates with hCG-induced testosterone secretion, and that cAMP and Ca(2+)-dependent pathway participates in the expression of protooncogene.
本研究旨在探讨反义c-myb寡脱氧核苷酸（ODN）对离体大鼠睾丸间质细胞中hCG诱导的睾酮分泌的影响。同时观察了cAMP、Ca(2+)和放线菌酮（CYX）对c-Myb蛋白表达和睾酮分泌的影响。结果显示，反义c-myb ODN以剂量依赖的方式抑制离体大鼠睾丸间质细胞中hCG诱导的睾酮分泌。同时，睾丸间质细胞中Myb的积分光密度免疫染色也显著降低。无义tat ODN对睾丸间质细胞无影响。进一步实验表明，二丁酰环磷腺苷钙（dbcAMP，100 μmol/L）明显增加hCG诱导的睾丸间质细胞睾酮分泌及Myb的积分光密度（IOD）免疫染色。钙通道阻滞剂维拉帕米（10 μmol/L）和蛋白质合成抑制剂放线菌酮（50 μg/ml）降低了c-Myb的免疫染色，也降低了离体大鼠睾丸间质细胞中hCG诱导的睾酮分泌。结果表明，c-myb与hCG诱导的睾酮分泌密切相关，且cAMP和Ca(2+)依赖途径参与原癌基因的表达。
