摘要
目的 本研究拟通过反义技术观察c fosASODNs对hCG诱导大鼠睾丸间质细胞睾酮分泌及睾酮合成过 程中限速酶表达水平的变化,并探讨其作用机制。方法 (1)放射免疫方法研究c fosASODNs对hCG诱导大鼠睾 丸间质细胞睾酮分泌的影响。(2)用免疫组织化学方法观察离体大鼠间质细胞Fos蛋白的变化。(3)用RT PCR 法观察在睾酮合成过程中大鼠间质细胞P450C17mRNA表达水平的变化。结果 (1)1.2×10-2IU/mlhCG可显著 性地增加间质细胞睾酮的分泌(P<0.01),并使c Fos蛋白染色阳性的间质细胞百分率和P450C17mRNA表达水 平显著性地升高(P<0.01)。(2)c fosASODNs呈剂量依赖性地抑制hCG诱导的离体间质细胞的睾酮分泌,同时 使c Fos蛋白染色阳性的间质细胞百分率下降,而无义tatODN没有相应作用。(3)当二丁酰cAMP与c fosA SODNs作用时可明显逆转c fosASODNs对hCG诱导间质细胞睾酮分泌的抑制作用,同时c Fos蛋白染色阳性的 间质细胞百分率和P450C17mRNA表达又恢复至接近hCG刺激水平。(4)维拉帕米(10-6mol/L)对hCG诱导的 大鼠间质细胞睾酮的分泌及c Fos蛋白染色阳性的间质细胞百分率均未见明显改变。结论 c fos参与hCG诱导 大鼠间质细胞睾酮的分泌,其机制很可能是通过cAMP PKA依赖性途径使c fos癌基因表达增?
Objective The effects of c-fos antisense oligodeoxynucleotides(c-fos ASODNs) on the hCG-induced testosterone secretion and the expression of restrictive enzyme of testosterone synthesis were investigated in isolated rat leydig cells,the possible mechanism involved in the process was also explored.Methods (1)The effects of c-fos ASODNs on hCG-induced testosterone secretion were measured by radioimmunoassay.(2)C-Fos protein was detected in isolated rat leydig cells by immunohistochemical method.(3)The expression of P450 C17mRNA was observed during testosterone synthesis by RT-PCR.Results (1)hCG(1.2×10 -2 IU/ml)significantly increased the secretion of testosterone ,the percentage of positive staining leydig cells for c-fos protein and the expression of P450 C17mRNA in isolated rat Leydig cells(P<0.01).(2) C-fosASODNs inhibited hCG-induced testosterone secretion in a dose-dependent manner and the percentage of positive staining leydig cells for c-fos protein also remarkably decreased,nonsense tat ODN had no similar effects on leydig cells.(3)Further experiments showed that dbcAMP(10 -4 mol/L) could reverse the inhibitory effects of c-fos ASODNs for hCG-induced testosterone secretion,and increased the percentage of positive staining leydig cells for c-fos protein and the expression of P450 C17mRNA.(4)Verapamil(1.0×10 -6 mol/L)could not significantly increased the secretion of testosterone and the percentage of positive staining cells for c-fos protein on hCG-induced leydig cells.Conclusions It is suggested that c-fos proto-oncogene correlates the hCG-induced testosterone secretion,and the mechanism is possible to enhance the expression of c-fos proto-oncogene by cAMP-dependent protein kinase A pathway,which in turn activates testosterone synthetase-the expression of P450 C17mRNA.
出处
《江西医学院学报》
2005年第1期24-27,共4页
Acta Academiae Medicinae Jiangxi
基金
江西省自然科学基金课题(NO.0040069)
