Beta-adrenergic receptors are involved in histamine-induced secretion of proopiomelanocortin-derived peptides and prolactin in rats.
The neurotransmitter histamine (HA) is involved in central regulation of secretion of prolactin (PRL) and the proopiomelanocortin (POMC)-derived peptides adrenocorticotropin (ACTH), beta-endorphin (beta-END) and alpha-melanocyte-stimulating hormone (alpha-MSH). The effect of HA on POMC-derived peptides and PRL release is, at least in part, indirect and may involve activation of catecholaminergic systems. Therefore, we investigated the effect of beta-adrenergic receptor blockade on HA or HA agonist-induced release of ACTH, beta-END, alpha-MSH and PRL. Central administration of HA, the H1-receptor agonist 2-thiazolylethylamine (2-TEA) or the H2-receptor agonist 4-methylhistamine (4-MeHA) stimulated the secretion of ACTH, beta-END, alpha-MSH and PRL. Pretreatment with the beta-adrenergic antagonist propranolol inhibited secretion of the POMC peptides in response to HA, 2-TEA or 4-MeHA. Propranonol only inhibited the PRL response to HA or 2-TEA, but had no effect on the PRL response to 4-MeHA. Administration of the beta-receptor agonist isoproterenol stimulated ACTH, beta-END, alpha-MSH and PRL two to five-fold. This effect was totally blocked by pretreatment with propranolol. We conclude that HA-induced secretion of POMC-derived peptides from the anterior and intermediate lobe of the pituitary gland and of PRL from the anterior lobe is, at least in part, mediated via catecholamines. beta-Adrenergic receptors are involved in the mediation of the POMC response to H1- as well as H2-receptor activation, whereas beta-receptors are involved only in the mediation of the PRL response to H1-receptor activation.
Department of Medical Physiology, Panum Institute, University of Copenhagen, Denmark.
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A
Kjaer
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Knigge
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Matzen
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Warberg
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000324:Adrenocorticotropic Hormone / Q000378:metabolism*; D000818:Animals; D004347:Drug Interactions; D006632:Histamine / Q000494:pharmacology*; D017442:Histamine Agonists / Q000494:pharmacology; D008297:Male; D010902:Pituitary Gland / Q000378:metabolism*; D011388:Prolactin / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D011943:Receptors, Adrenergic, beta / Q000378:metabolism*; D000521:alpha-MSH / Q000378:metabolism*; D001615:beta-Endorphin / Q000378:metabolism*
D000319:Adrenergic beta-Antagonists; D017442:Histamine Agonists; D011943:Receptors, Adrenergic, beta; D000521:alpha-MSH; D001615:beta-Endorphin; D006632:Histamine; D000324:Adrenocorticotropic Hormone; D011388:Prolactin