14 Since anterior pituitary expresses prolactin receptors, prolactin secreted by lactotropes could 15 exert autocrine or paracrine actions on anterior pituitary cells. In fact, it has been observed that 16 prolactin inhibits its own expression by lactotropes. Our hypothesis is that prolactin participates 17 in the control of anterior pituitary cell turnover. In the present study we explored the...

Since anterior pituitary expresses prolactin receptors, prolactin secreted by lactotropes could exert autocrine or paracrine actions on anterior pituitary cells. In fact, it has been observed that prolactin inhibits its own expression by lactotropes. Our hypothesis is that prolactin participates in the control of anterior pituitary cell turnover. In the present study, we explored the action of ...

We investigated the role of cortical actin filaments (F-actin) in the regulation of PRL secretion in cultured normal anterior pituitary cells. F-actin dynamics were evaluated by fluorescence microscopy, and PRL secretion from attached cells was measured by the reverse hemolytic plaque assay. F-actin localized to the periphery of lactotropes. PRL-releasing factors such as TRH, vasoactive intesti...

We have previously shown that transforming growth factor beta 1 (TGF-beta 1) receptor and TGF-beta type II receptor (T beta R-II) are produced in lactotropes, and that TGF-beta 1 inhibits the growth of these anterior pituitary cells by an autocrine mechanism. To study the changes of the expression and function of this growth factor during tumorigenesis, we have measured the levels of TGF-beta 1...

Tissue homeostasis results from a balance between cell proliferation and cell death by apoptosis. Estradiol affects proliferation as well as apoptosis in hormone-dependent tissues. In the present study, we investigated the apoptotic response of the anterior pituitary gland to lipopolysaccharide (LPS) in cycling female rats, and the influence of estradiol in this response in ovariectomized (OVX)...

it is well known that several plant extracts have a lactogenic effect. this response may be inducedthrough the stimulation of prolactin release from lactotrope cells. a partial purification of the activecompound indicated that it is rich in pectin and β-glucan. these materials stimulate secretion of prolactinfrom hypophyseal fragments. in the present study, the effect of β-glucan on the secreti...