Prolactin secretion

The class III cytokine receptor family includes two TNE receptors, the low affinity NGE receptor and 7-ceU surface recognition sites that appear to play a role in proliferation, apoptosis, and immunodeficiency. TNE-a (- 17, 000 protein) is produced by astrocytes and microglia and can induce fever, induce slow-wave sleep, reduce feeding, stimulate prostaglandin synthesis, stimulate corticotrophin-releasing factor and prolactin secretion, and reduce thyroid hormone secretion. TNE-a stimulates IL-1 release, is cytotoxic to oligodendrocytes, and reduces myelination this has been impHcated in multiple sclerosis and encephalomyelitis. Astrocyte TNE-a receptors mediate effects on IL-6 expression and augment astrocytic expression of MHC in response to other stimulants such as lEN-y. 

Importantly, they achieve this without inducing extrapyramidal side-effects or increasing prolactin secretion, which are real problems with neuroleptics. These results have been borne out by preliminary clinical trials of buspirone, used in combination with neuroleptics, and several novel S-HTja agonists (e.g. BSF 190555) are currently under development for this clinical application (Meltzer 1999). 

Nevertheless it must also be expected that anything which increases DA function not only controls extrapyramidal function but also reproduces the other central effects of DA i.e. vomiting, a reduction in prolactin secretion and some psychotic manifestations. In excess it may also cause dyskinesias. Despite these problems, the therapy of PD is one of the success stories of neurology. 

Bronson F. and Maruniak J.A. (1976). Differential effects of male stimuli on follicle stimulating hormone, luteinising hormone and prolactin secretion in prepubertal female mice. Endocrinology 98, 1101-1108. 

Review the available diagnostic data to determine pituitary tumor size and location. Determine if the patient has a coexisting prolactin-secreting tumor. Determine if the tumor extends toward the optic chiasm or if it is continuous on the optic tracts. 

Headache and compromised or loss of vision caused by the prolactin-secreting tumor and its close proximity to the optic structures. 

Increased body weight may be associated with prolactin-secreting pituitary tumor. 

Anterior pituitary Pituitary prolactin-secreting adenoma Hypothyroidism Med ications—antipsychotics, verapamiI T Prolactin suppresses HPO axis TRH causing T prolactin, other abnormalities T Prolactin suppresses HPO axis... 

The release of prolactin from the adenohypophysis is normally inhibited by prolactin-inhibiting hormone (PIH, dopamine) from the hypothalamus. Prolactin secretion is also controlled by prolactin-releasing factor (PRF). The release of PRF from the hypothalamus is mediated by reflexes elicited by suckling and breast stimulation. 

Benker G., Jaspers C., Hausler G., Reinwein D. (1990). Control of prolactin secretion. 

Andersson K., Siegel R., Fuxe K., Eneroth P. (1983). Intravenous injections of nicotine induce very rapid and discrete reductions of hypothalamic catecholamine levels associated with increases of ACTH, vasopressin and prolactin secretion. Acta Physiol. Scand. 118, 35-40. 

The answer is d. (Hardman, pp 1371-13720 High prolactin levels in the serum result in amenorrhea, for reasons that are not known. Bromocriptine inhibits prolactin secretion through its dopaminergic action This compound, a semisynthetic ergot derivative, appears to be a dopamine receptor agonist. It is administered orally to the patient and, in most cases, menses occurs after a month of therapy. 

Pinilla L, Gonzalez LC, Tena-Sempere M, Aguilar E (2001) Evidence for an estrogenlike action of raloxifene upon the hypothalamic-pituitary unit raloxifene inhibits luteinizing hormone secretion and stimulates prolactin secretion in ovariectomized female rats. Neurosci Lett 311 149-152... 

It became known to suppress prolactine secretion, and it is therefore a useful tool in the treatment of prolactine dependent disorders, such as galactorrhea associated with hyperprolactinemia and postpartum, as well as certain kinds of sterility (3 - 9). In more elevated doses, the drug is a potent antiparkinsonicum. In addition, there is recent evidence of bromocriptine playing an important role in the trace heavy metals balance of the brain (10). 

Neuroendocrine Reduces testicular production of testosterone Enhances target responsivity to gonadotropins Reduces LH and prolactin secretion Increases adrenocorticotrophic hormone levels Increases corticosterone levels... 

Demisch L, Neubauer M. (1979). Stimulation of human prolactin secretion by mescaline. Psychopharmacology (Berlin). 64(3) 361-63. 

Giacomelli S, Palmery M, Romanelli L, Cheng CY, Silvestrini B. (1998). Lysergic acid diethylamide (LSD) is a partial agonist of D2 dopaminergic receptors and it potentiates dopamine-mediated prolactin secretion in lactotrophs in vitro. Life Sci. 63(3) 215-22. 

Prolactin secretion, at least in experimental animals, is increased following chronic lithium treatment, probably as a consequence of the enhanced sensitivity of posts)maptic 5-HT receptors and the decreased sensitivity of dopamine receptors. In patients on therapeutic doses of the drug, however, the plasma prolactin levels would not appear to be markedly altered. There is little evidence that circulating gonadotrophin concentrations are affected by therapeutic doses of lithium. 

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