雌激素诱发大鼠原位与移植垂体催乳素瘤中催乳素基因与TGFα和TGF …

利用本实验室建立的１７β－雌二醇诱致Ｓｐｒａｇｕｅ－Ｄａｗｌｅｙ（ＳＤ）大鼠原位垂体和异体移植于肾囊的垂体同时形成催乳素瘤的动物模型,采用Ｎｏｒｔｈｅｍ印迹杂交方法,我们观察了Ｅ２长期作用（１２０ｄ）后诱发的原位与移植垂体ＰＲＬ瘤中ＰＲＬ基因和两种转化生长因子ＴＧＦα和ＴＧＦβ１基因表达水平的改变。结果表明：在Ｅ２长期作用后,原位垂体与异体移植于肾囊,从而远离下丘脑的垂体均可形成垂体ＰＲＬ瘤;原位

Expression of prolactin, TGF alpha and TGF beta 1 genes in estrogen-induced eutopic and ectopic pituitary prolactin-secreting tumors of rats

The Sprague-Dawley (SD) rat bearing a heteroplasted pituitary underneath renal capsule was used to observe differential expression of prolactin (PRL), transforming growth factor alpha (TGF alpha) and transforming growth factor beta 1 (TGF beta 1) genes during the formation of pituitary prolactin-secreting tumor (prolactinoma) induced by 17 beta-estradiol (E2). Our results indicated that in both eutopic and ectopic pituitaries disconnected from hypothalamus formed simultaneously PRL-secreting tumors after the rats treated with E2 for 120 days in vivo, which was accompanied by overexpression of PRL gene (P < 0.05-0.01). The PRL mRNA level was higher in eutopic prolactinoma than that in ectopic prolactinoma (P < 0.05). Overexpression of TGF alpha and TGF beta 1 genes were also detected in eutopic prolactinoma. However, the expression of TGF alpha and TGF beta 1 genes in ectopic prolactinoma was similar to that in normal pituitary. It is suggested that TGF alpha and TGF beta 1 may be involved in prolactinoma tumorigenesis of eutopic pituitary. However, the mechanism mediating eutopic and ectopic prolactin-secreting tumor formation seems different.