血管活性肠肽和组异肽对催乳素基因转录调控作用的比较

The Comparison of Vasoactive Intestinal Polypeptide(VIP) and Peptide Histidine isoleucine(PHI)in the control of Prolactin Gene TranscriptionDi anke .

实验用ＳＤ大鼠垂体前叶细胞原代培养及原位杂交方法，研究不同浓度的血管活性肠肽（Ｖａ－ｓｏａｃｔｉｖｅＩｎｔｅｓｔｉｎａｌＰｏｌｙｐｅｐｔｉｄｅ，ＶＩＰ）或组异肽（ＰｅｐｔｉｄｅＨｉｓｔｉｄｉｎｅＩｓｏｌｅｕｃｉｎｅ，ＰＨＩ）对催乳素（Ｐｒｏｌａｃｔｉｎ，ＰＲＬ）基因转录水平的调节。结果表明，经不同浓度的ＶＩＰ或ＰＨＩ与垂体前叶细胞一起孵育２４ｈ后，胞内ＰＲＬｍＲＮＡ随ＶＩＰ及ＰＨＩ浓度的加大而升高（Ｐ＜０．０１）。１０￣（－８）、１０￣（－７）、１０￣（－６）ｍｏｌ／Ｌ的ＶＩＰ分别使胞内ＰＲＬｍＲＮＡ升高为对照组的３．０、４．０、４．７倍；１０￣（－９）、１０￣（－８）、１０￣（－７）ｍｏｌ／Ｌ的ＰＨＩ则分别使细胞内ＰＲＬｍＲＮＡ升高为对照组的２．５、３．８、５．５倍。进一步分析表明，虽然ＶＩＰ及ＰＨＩ均促进ＰＲＬ基因转录，但它们的作用强度不同。１０￣（－８）、１０￣（－７）ｍｌｏ／Ｌ的ＰＨＩ分别使细胞内ＰＲＬｍＲＮＡ的含量升高为相同浓度ＶＩＰ的１．５倍及１．６倍（Ｐ＜０．０５），提示ＰＨＩ促进ＰＲＬ基因转录的作用比ＶＩＰ强。

he effects of Vasoactive Intestinal polypeptide(VIP)and Peptide Histidine Isoleucine(PHI)on the reg-uiation of prolactin(PRL) gene transcription of anterior pituitary cells in culture of Sprague-Dawley(SD)ratswere evaluated by in situ hybridization using a DIG-labelled PRL cDAN probe. Our results indicated that thePRL mRNA levels increased when the anterior pituitary cells were incubated with VIP or PHI for 24h(P<0. 01).The concentrations of PRL mRNA in 10￣(-8),10￣(-7),10￣(-6)mol/L VIP groups were 3.0,4.0,4.7fold of con-trol group respectively;were 2.5,3.8,5. 5 fold of control group in 10￣ (-9),10￣(-8),10￣(-7)mol/L PHI groups respec-tively. Thus,the stimulatory effects of VIP and PHI on the PRL gene transcription seemed to be dose-depen-dent iri this experiment. A further analysis indicated that the stimulatory effect of PHI on PRL gene transcrip-tion was stronger than that of VIP. Under same coniditons, the concentrations of PRL mRNA in 10￣(-8), 10￣ (-7)mol/L PHI groups were 1.5,1. 6 fold of VIP in 10￣(-,10￣(-7)7mol/L groups respectively(P<0. 05)。