The hypothalamic paraventricular nucleus has a pivotal role in regulation of prolactin release in lactating rats.

The affect of paraventricular nucleus (PVN) lesions on PRL secretory response to suckling was studied in adult female rats. Basal levels of PRL were similar in the control and lesioned groups. Substantial decreases in PRL levels occurred after separation of pups from their mothers in the control as well as lesioned animals. When mothers and pups were reunited, the circulating PRL concentrations of the control groups rose immediately from basal values of 50-100 micrograms/liter to reach peaks of 450-550 micrograms/liter. PVN lesions significantly decreased the suckling-induced rise of PRL levels. Furthermore, PVN lesions abolished the high amplitude, episodic pattern of PRL release in continuously lactating rats. These findings are consistent with the view that PVN neurons produce PRL releasing factor(s), which is (are) required for normal secretory patterns of PRL in lactating rats.

[1]  G. Nagy,et al.  Episodic prolactin and growth hormone secretion not related to the actual suckling activity in lactating rats. , 1986, The Journal of endocrinology.

[2]  M. Molitch,et al.  Vasoactive intestinal peptide is a physiological mediator of prolactin release in the rat. , 1985, Endocrinology.

[3]  W. Samson,et al.  Recent studies on the role of brain peptides in control of anterior pituitary hormone secretion , 1984, Peptides.

[4]  G. Nagy,et al.  Time course of the litter removal-induced depletion in plasma prolactin levels of lactating rats. An immediate full blockade of the hormone release after separation. , 1983, Neuroendocrinology.

[5]  T. Hökfelt,et al.  Effect of the peptide PHI-27 on prolactin release in vitro. , 1983, Neuroendocrinology.

[6]  W. Samson,et al.  Hypothalamic and pituitary sites of action of oxytocin to alter prolactin secretion in the rat. , 1983, Endocrinology.

[7]  G. Fink,et al.  Release of thyrotropin releasing hormone into hypophysial portal blood is high relative to other neuropeptides and may be related to prolactin secretion , 1982, Brain Research.

[8]  M. Palkovits,et al.  Thyrotropin releasing hormone in the median eminence is in processes of paraventricular nucleus neurons , 1982, Neuropeptides.

[9]  G. Béraud,et al.  Effect of vasoactive intestinal peptide (VIP) on the release of adenohypophyseal hormones from purified cells obtained by unit gravity sedimentation. Inhibition by dexamethasone of vip-induced prolactin release. , 1980 .

[10]  M. Ruberg,et al.  Stimulation of in vitro prolactin release by vasoactive intestinal peptide. , 1980, Neuroendocrinology.

[11]  J. Clemens,et al.  Effect of vasoactive intestinal polypeptide on prolactin release in vitro. , 1979, Life sciences.

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

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

[14]  J. Tramezzani,et al.  The neural input of the milk ejection reflex in the hypothalamus. , 1973, Endocrinology.

[15]  J. Kiss,et al.  Vasoactive intestinal peptide-containing neurons in the paraventricular nucleus may participate in regulating prolactin secretion. , 1985, Proceedings of the National Academy of Sciences of the United States of America.

[16]  L W Swanson,et al.  Hypothalamic integration: organization of the paraventricular and supraoptic nuclei. , 1983, Annual review of neuroscience.

[17]  J. D. Neill,et al.  Neuroendocrine control of prolactin secretion. , 1983, Annual review of physiology.