Autocrine and/or paracrine action of vasoactive intestinal peptide on thyrotropin-releasing hormone induced prolactin release.

Several in vitro studies have demonstrated that vasoactive intestinal peptide (VIP) modulates basal PRL release in normal and hypothyroid anterior pituitary (AP) cells through an autocrine or paracrine action. As thyroid hormone is an important factor in the regulation of pituitary VIP synthesis and secretion, we analyzed the influence of the absence of thyroid hormone on basal PRL release in vitro to study whether the release of PRL induced by TRH might be mediated by a local action of pituitary VIP. When normal AP cells were cultured in a medium supplemented with a near-physiological concentration of free T2 (0.5 nM), basal PRL and VIP release decreased and PRL secretion was not altered by the blockade of VIP action. This finding allowed us to establish the culture conditions in which basal PRL secretion is apparently not under VIP influence. Consequently, we were able to study whether pituitary VIP may be implicated in TRH-induced PRL release. TRH (100 nM) increased PRL and VIP release in a parallel manner and decreased PRL and VIP intracellular content in incubations from 15-180 min. When AP cells wee incubated simultaneously with TRH and a VIP receptor antagonist, TRH-induced PRL release decreased when incubation lasted more than 30 min, whereas the depletion of PRL intracellular content induced by TRH was unchanged. TRH also slightly increased VIP messenger RNA levels at 3 and 24 h, but PRL messenger RNA levels were not modified. These data demonstrate that pituitary VIP participates in in TRH-induced PRL release and that the effect of thyroid hormone on basal pituitary VIP secretion should be borne in mind when studies on its effect, through autocrine and/or paracrine mechanisms, on PRL release stimulated by PRL-releasing factors are conducted.

[1]  J. Balsa,et al.  Induction of vasoactive intestinal peptide gene expression and prolactin secretion by insulin-like growth factor I in rat pituitary cells: evidence for an autoparacrine regulatory system. , 1994, Endocrinology.

[2]  F. Kimura,et al.  Lactotrophs secreting small amounts of prolactin reveal great responsiveness to thyrotropin-releasing hormone: analysis by the sequential cell immunoblot assay. , 1992, Endocrinology.

[3]  M. Surks,et al.  Role of L-thyroxine in nuclear thyroid hormone receptor occupancy and growth hormone production in cultured GC cells. , 1991, The Journal of clinical investigation.

[4]  J. Vincent,et al.  Functional Lactotroph Heterogeneity in Lactating Rats and in vitro Modification by 17Beta‐Estradiol , 1990, Journal of neuroendocrinology.

[5]  O. Rorstad,et al.  Receptors for vasoactive intestinal peptide in rat anterior pituitary glands: localization of binding to lactotropes. , 1990, Endocrinology.

[6]  K. Kovacs,et al.  Effects of propylthiouracil on growth hormone and prolactin messenger ribonucleic acids in the rat pituitary. , 1990, Laboratory investigation; a journal of technical methods and pathology.

[7]  A. Arimura,et al.  Presence of immunoreactive vasoactive intestinal polypeptide in anterior pituitary of normal male and long term estrogen-treated female rats: a light microscopic immunohistochemical study. , 1990, Endocrinology.

[8]  S. Reichlin,et al.  Pituitary vasoactive intestinal peptide regulates prolactin secretion in the hypothyroid rat. , 1989, Neuroendocrinology.

[9]  R. Lechan,et al.  Thyroid hormone regulates vasoactive intestinal peptide (VIP) mRNA levels in the rat anterior pituitary gland. , 1989, Endocrinology.

[10]  S. Reichlin,et al.  Synthesis and secretion of vasoactive intestinal peptide by rat fetal cerebral cortical and hypothalamic cells in culture. , 1989, Endocrinology.

[11]  R. Mogg,et al.  Oxytocin mediates the hypothalamic action of vasoactive intestinal peptide to stimulate prolactin secretion. , 1989, Endocrinology.

[12]  R. Lechan,et al.  Vasoactive intestinal peptide in the anterior pituitary is increased in hypothyroidism. , 1989, Endocrinology.

[13]  T. Lemarchand-Béraud,et al.  The secretory activity of the tuberoinfundibular dopaminergic neurons is modulated by the thyroid status in the adult rat: consequence on prolactin secretion. , 1987, Neuroendocrinology.

[14]  F. R. Boockfor,et al.  Functional variations among prolactin cells from different pituitary regions. , 1987, Endocrinology.

[15]  T. Garthwaite,et al.  Vasoactive intestinal polypeptide is synthesized in anterior pituitary tissue. , 1986, Endocrinology.

[16]  J. Franklyn,et al.  Tri-iodothyronine and phenytoin reduce prolactin messenger RNA levels in cultured rat pituitary cells. , 1986, The Journal of endocrinology.

[17]  F. Sánchez Franco,et al.  Direct action of opioid peptides and naloxone on gonadotropin secretion by cultured rat anterior pituitary cells. , 1986, Life sciences.

[18]  P. Albert,et al.  Relationship of thyrotropin-releasing hormone-induced spike and plateau phases in cytosolic free Ca2+ concentrations to hormone secretion. Selective blockade using ionomycin and nifedipine. , 1984, The Journal of biological chemistry.

[19]  R. Evans,et al.  Polypeptide hormone regulation of gene expression. Thyrotropin-releasing hormone rapidly stimulates both transcription of the prolactin gene and the phosphorylation of a specific nuclear protein. , 1983, The Journal of biological chemistry.

[20]  K. Gautvik,et al.  Thyroliberin receptor binding and adenylyl cyclase activation in cultured prolactin-producing rat pituitary tumor cells (GH cells). , 1983, The Journal of biological chemistry.

[21]  M. Greer,et al.  In vitro TSH and PRL secretion from eutopic and heterotopic rat pituitaries: effects of hypothyroidism. , 1983, The American journal of physiology.

[22]  R. Maurer.  Thyroid hormone specifically inhibits prolactin synthesis and decreases prolactin messenger ribonucleic acid levels in cultured pituitary cells. , 1982, Endocrinology.

[23]  G. Morel,et al.  Ultrastructural evidence for endogenous vasoactive intestinal peptide-like immunoreactivity in the pituitary gland. , 1982, Neuroendocrinology.

[24]  A. von zur Mühlen,et al.  Effects of tri-iodothyronine, thyroxine and isopropyl-di-iodothyronine on thyroid-stimulating hormone in serum and pituitary gland and on pituitary concentrations of prolactin, growth hormone, luteinizing hormone and follicle-stimulating hormone in hypothyroid rats. , 1980, The Journal of endocrinology.

[25]  G. Greeley,et al.  Studies of the neural mechanisms by which hypothyroidism decreases prolactin secretion in the rat , 1980, Brain Research.

[26]  D. Bataille,et al.  Vasoactive intestinal peptide (VIP) stimulates prolactin (PRL) release and cAMP production in a rat pituitary cell line (GH3/B6). Additive effects of VIP and TRH on PRL release , 1979, FEBS letters.

[27]  P. de Neef,et al.  VIP activation of rat anterior pituitary adenylate cyclase , 1979, FEBS letters.

[28]  S. Said,et al.  Radioimmunologic localization of vasoactive intestinal polypeptide in hypothalamic and extrahypothalamic sites in the rat brain , 1979, Neuroscience Letters.

[29]  S. Said,et al.  Vasoactive intestinal polypeptide: release into hypophyseal portal blood. , 1979, Life sciences.

[30]  H. Imura,et al.  Prolactin release by vasoactive intestinal polypeptide in rats. , 1978, Endocrinology.

[31]  K. Gautvik,et al.  A possible role of cyclic AMP in mediating the effects of thyrotropin-releasing hormone on prolactin release and on prolactin and growth hormone synthesis in pituitary cells in culture. , 1976, Endocrinology.

[32]  R. Guillemin,et al.  TRF and thyroid hormones on prolactin secretion by rat anterior pituitary cells in vitro. , 1973, Endocrinology.

[33]  A. Tashjian,et al.  Thyrotropin releasing hormone: direct evidence for stimulation of prolactin production by pituitary cells in culture. , 1971, Biochemical and biophysical research communications.

[34]  J. D. Neill,et al.  Autocrine control of prolactin secretion by vasoactive intestinal peptide. , 1988, Endocrinology.

[35]  L. Keith,et al.  Dynamics of thyrotropin-releasing hormone-induced thyrotropin and prolactin secretion by acutely dispersed rat adenohypophyseal cells. Evidence for 'all-or-none' secretion by heterogeneous secretory units, each with a specific response threshold. , 1986, Neuroendocrinology.

[36]  T. Garthwaite,et al.  Antisera to vasoactive intestinal polypeptide inhibit basal prolactin release from dispersed anterior pituitary cells. , 1986, Neuroendocrinology.

[37]  M. Montminy,et al.  In Situ Hybridization of Somatostatin and Vasoactive Intestinal Peptide mRNA in the Rat Nervous System , 1986 .

[38]  R. Treisman,et al.  Transcription maps of polyoma virus-specific RNA: analysis by two-dimensional nuclease S1 gel mapping. , 1980, Methods in enzymology.

[39]  W. Wilfinger,et al.  Maintenance of separated rat pituitary mammotrophs in cell culture. , 1976, Endocrinology.