geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

2-Hydroxyoestradiol acutely inhibits prolactin secretion from the superfused pituitary glands of normal female rats: evidence for a cyclical effect


, : 2-Hydroxyoestradiol acutely inhibits prolactin secretion from the superfused pituitary glands of normal female rats: evidence for a cyclical effect. Journal of Endocrinology 111(2): 199-204

Catecholoestrogens are naturally occurring metabolities of oestrogens which are found in brain tissue and for which a neuroendocrine role has been postulated. However, reports of their effects on prolactin secretion are ambiguous and as yet no defined function has been attributed to them. The effects of 2-hydroxyoestradiol (2-OHE2) and dopamine on the release of prolactin in vitro by perfused pituitary glands from normal adult female rats at different stages of the oestrous cycle have been investigated. The purity and stability of the 2-OHE2 preparation before and after exposure to pituitary tissue was confirmed by radioenzymatic assay and subsequent thin-layer chromatography. Dopamine (500 nmol/l, 100 nmol/l) was found consistently to suppress release by 60%; this effect was immediate and reversible upon removal of the dopamine. In contrast, the effects of 2-OHE2 (10 nmol/l, 100 nmol/l) were found to vary during the cycle. No effect on prolactin release was evident during either dioestrus or pro-oestrus, but during oestrus a similar, though less potent, suppression of prolactin secretion to that of dopamine was observed (35% suppression compared with controls). The cyclical variation in the suppressive effect of 2-OHE2 on prolactin secretion in the female rat is compatible with a postulated neuroendocrine role for this catecholoestrogen.

US$19.90

PMID: 3794579

DOI: 10.1677/joe.0.1110199


Other references

Zhao, Y-l.; Mao, J-q.; Huang, Y-z.; Liu, J-w., 1984: Trilobites of the Lower Cambrian Huanglianba Formation from Zhongxin of Kaiyang, Guizhou. Acta Palaeontologica Sinica, 236: 755-763

Bassirirad, H.T.omas, R.; Reynolds, J.; Strain, B., 1996: Differential responses of root uptake kinetics of NH4+ and NO3- to enriched atmospheric CO2 concentration in field-grown loblolly pine. The nitrogen requirement of plants is predominantly supplied by NH4(+) and/or NO3(-) from the soil solution, but the energetic cost of uptake and assimilation is generally higher for NO3(-) than for NH4(+). We found that CO2 enrichment of the atmo...

Men'shikov V.V., 1976: Determination of total lipids in blood serum by color reaction with sulfo phospho vanillin reagent. Laboratornoe Delo: 375

Manzini, S.; Maggi, C.A.; Meli, A., 1985: Further evidence for involvement of adenosine-5'-triphosphate in non-adrenergic non-cholinergic relaxation of the isolated rat duodenum. The nature of the inhbitory non-adrenergic non-cholinergic (NANC) neurotransmitter responsible for neurogenic relaxation of rat duodenum was studied with in vitro techniques. Adenosine 5'-triphosphate (ATP)(1 mM), gamma-aminobutyric acid (GAB...

Weinstock, M., 1997: Possible role of the cholinergic system and disease models. Memory impairment associated with the loss of cortical cholinergic neurons in AD has stimulated the development of animal models based on blockade or destruction of these systems. Strategies include mechanical lesions, local injection of excitotox...

Krams T.F., 1993: Gravel exploitation and restoration of extraction zones in the Netherlands. Tierra y Tecnologia 4: 50-54

Avni, J.; Bruderman, I., 1969: The effect of amitriptyline on pulmonary ventilation and the mechanics of breathing. Psychopharmacologia 14(3): 184-192

Traxer, O.; Lechevallier, E.; Saussine, C.; Daudon, M.; Haymann, J-P., 2008: Metabolic syndrome and urolithiasis. A new concept for the urologist. Progres en Urologie 18(12): 828-831

Nice, M.M., 1946: Jan Joost ter Pelkwyk, naturalist. Chicago Naturalist, 9: 27-35

Li, T.-Sheng; Komota, T.; Ohshima, M.; Qin, S.-Lan; Kubo, M.; Ueda, K.; Hamano, K., 2008: TGF-beta induces the differentiation of bone marrow stem cells into immature cardiomyocytes. Transforming growth factor-beta(1) (TGF-beta(1)) was found to induce the myogenic differentiation of bone marrow stem cells (BMSC). We investigated the morphological and electrophysiological properties of differentiated cells, and the mechanisms r...