Inhibition of prolactin

When tested on prolactin release in isolated mammatrophs of bovine anterior pituitary, apomorphine appeared a full agonist (inhibiting release) while antagonism of the inhibition of prolactin release by the neuroleptics showed a potency more similar to that for binding than for blocking cAMP production. Also the inhibition of prolactin... 

Control (inhibition) of prolactin release Tuberoinfundibular tract from A12 in the arcuate nucleus of the median eminence to pituitary Humans Hypoprolactaemia Humans Hyperprolactaemia Galactorrhoea Amenorrhoea D2 ... 

Dopamine A few studies have examined the dopaminergic effects of LSD. The affinity of LSD for D2 receptors is similar to its affinity for 5-HT2 sites, and it has a slightly lower affininty for D1 receptors (Watts et al. 1995). LSD has partial agonist effects at D2 receptors as seen in the inhibition of prolactin release (Giacomelli et al. 1998). Neuroleptic drugs are also used clinically to terminate an LSD experience. Thus, the effects of LSD on dopaminergic function may contribute to its hallucinogeinc effects. 

Dopamine A. As the precursor of norepinephrine and epinephrine (p. 184), dopamine is found in sympathetic (adrenergic) neurons and adrenomedullary cells. In the CNS, dopamine itself serves as a neuromediator and is implicated in neostriatal motor programming (p. 188), the elicitation of emesis at the level of the area postrema (p. 330), and inhibition of prolactin release from the anterior pituitary (p. 242). 

No preparation of prolactin is available for use in prolactin-deficient patients. For patients with symptomatic hyperprolactinemia, inhibition of prolactin secretion can be achieved with dopamine agonists, which act in the pituitary to inhibit prolactin release. 

There are some other ergot derivatives known to suppress nidation of the fertilized egg in rats. This effect also seems to result from an inhibition of prolactin synthesis or, more specifically, from an increase... 

In 1978 we compared the structure activity requirements for the DA, (vascular DA) receptor with other putative DA receptors (1,4 )7 The limited SAR data available at that time supported the existence of at least two different DA receptors. DA-induced responses were divided into two categories on the basis of differences in agonist activity and potency series. The following phenomena appeared to be due to activation of DA2 receptors inhibition of norepinephrine release from the postganglionic sympathetic nerve inhibition of ganglionic transmission inhibition of prolactin release and emesis. Review of the current literature has not revealed exceptions to these correlations. 

Meller E, Puza T, Diamond J, Lieu HD, Bohmaker K. Comparative effects of receptor inactivation, 17 beta-estradiol and pertussis toxin on dopaminergic inhibition of prolactin secretion in vitro. J Pharmacol Exp Ther 1992 263 462-469. 

A variety of studies on the binding of labelled prolactin to cells or membrane preparations from immune tissues have been described, with rather variable results. In some cases, at least, substantial binding has been shown to membrane fractions from spleen and thymus and to human lymphocytes [21,120,121]. It has been reported that this binding can be enhanced or blocked by the immunosuppressive drug cyclosporin A [21,120-122], and a mechanism for this drug involving such inhibition of prolactin binding has been proposed. 

Foord SM, Peters JR, Dieguez C, Scanlon MF, Hall R (1983) Dopamine receptors on intact anterior pituitary cells in culture functional association with the inhibition of prolactin and thyrotropin. Endocrinology 772 1567-1577. 

Matsushita N, Kato Y, Katakami H, Shimatsu A, Yanaihara N, Imura H (1983) Inhibition of prolactin secretion by gastrin releasing peptide (GRP) in the rat. Proc Soc Exp Biol Med 772 118-121. 

Increased cAMP coronary, mesenteric) Inhibition of prolactin release... 

Ho, B.Y., Stadnicka, A., Prather, P.L., Buckley, A.R., Current, L.L., Bosnjak, Z.J., and Kwok, W-M. (2000) Cannabinoid CB, receptor-mediated inhibition of prolactin release and signaling mechanisms in GH4C1 cells. Endocrinology 141 1675-1685. 

Inhibition of growth hormone Stimulation of thyroid-stimulating hormone Stimulation of adrenocorticotropic hormone Tonic inhibition of prolactin secretion Follicular growth, estradiol production, spermatogenesis... 

Ergot alkaloids are adrenergic blocking agents. These compounds also inhibit lactation in animals by inhibition of prolactin release, a mammalian hormone responsible for mammary and milk production (Fliickiger, 1980 Stadler and... 

Recent interest in lergotrile (33) (Figure 7) stems from its putative dopaminergic activity and inhibition of prolactin secretion. Toxicity in clinical trials prompted the exploration of microbial transformation for producing less toxic derivatives. 

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