生长因子和雌激素对大鼠垂体前叶细胞增殖活性及催乳素？…

目的 观察外源性生长因子和雌激素对离体正常大鼠垂体前叶细胞增殖活性及催乳素基因表达的影响,并探讨生长因子与雌激素作用的关系。方法 应用无血清原代培养的大鼠垂体前叶细胞,分别采用荧光染色细胞ＤＮＡ的激光扫描共聚焦显策镜扫描,以及原位杂交方法,观察了１７β－雌二醇,表皮生长因子及转化生长因子β１对大鼠垂有叶细胞增殖活性和催乳素基因表达的影响。结果 生长因子或雌激叶细胞增殖活性和催乳素基因表达的影响。结

Effects of growth factors and estrogen on the proliferation and prolactin gene expression in anterior pituitary cells of rats

OBJECTIVE: Detect the effects of exogenous 17 beta-estradiol (E2), epidermal growth factor (EGF), and transforming growth factor beta 1 (TGF beta 1) on the proliferation and prolactin (PRL) gene expression in primary serum-free cultured anterior pituitary cells in vitro. METHODS: Laser scanning confocal microscopy (LSCM) and in situ hybridization in primary serum-free cultures of rat anterior pituitary cells were employed. RESULTS: After 36 hours incubation of the monolayer with E2(10(-8) mol/L) and EGF(10(-8) mol/L), DNA and PRL mRNA contents in the cells were increased significantly (P < 0.001); and when cells were co-incubated with E2 and EGF at the same time, the levels of DNA and PRL mRNA were higher than those treated with E2 or EGF alone (P < 0.01), respectively. TGF beta 1(2 ng/ml) treatment decreased the DNA and PRL mRNA contents significantly (P < 0.001). Its inhibitory effect was reduced at the presence of E2, the DNA and PRL mRNA levels in the cells were higher than those treated with TGF beta 1 alone (P < 0.001), but still lower than E2 alone treatment (P < 0.001). CONCLUSIONS: The results indicate that EGF and TGF beta 1 exerte stimulatory inhibitory effects, on cell proliferation and PRL gene expression in anterior pituitary cells of rats in both basal and E2-induced conditions. EGF and TGF beta 1 may be involoved in the regulation of proliferation and PRL gene expression in anterior pituitary cells in vivo; and also may be correlated with prolactin-secreting tumors formation induced by E2.