title: Dopamine D2 receptor effects on GABA(A) receptor expression may modify melanotrope peptide release.
abstract: Stimulation of melanotrope dopamine D2 receptors decreases mitotic rate, calcium channel activity, and the biosynthesis of several proteins. This study demonstrates that D2 receptor activation also affects GABA(A) receptor beta2/beta3 subunit immunoreactivity. Following chronic treatment with haloperidol, a D2 receptor antagonist, GABA(A) receptor immunoreactivity increased, whereas it decreased after chronic treatment with bromocriptine, a dopamine D2 receptor agonist. Thus, these data indicate that D2 function regulates GABA(A) receptor expression in melanotropes, a mechanism by which peptide release may be modified.
authors.affiliation: School of Biological Sciences, University of Missouri-Kansas City, 64110, USA.
authors.forename: S A
authors.initials: SA
authors.lastname: Sands
authors.forename: A L
authors.initials: AL
authors.lastname: de Blas
authors.forename: B M
authors.initials: BM
authors.lastname: Chronwall
mesh_terms: D000818:Animals; D001971:Bromocriptine / Q000494:pharmacology; D018491:Dopamine Agonists / Q000494:pharmacology; D018492:Dopamine Antagonists / Q000494:pharmacology; D065127:Dopamine D2 Receptor Antagonists; D006220:Haloperidol / Q000494:pharmacology; D007150:Immunohistochemistry; D008297:Male; D009074:Melanocyte-Stimulating Hormones / Q000378:metabolism*; D010902:Pituitary Gland / Q000187:drug effects / Q000502:physiology; D011333:Pro-Opiomelanocortin / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D017448:Receptors, Dopamine D2 / Q000819:agonists / Q000502:physiology*; D011963:Receptors, GABA-A / Q000502:physiology*
chemical_list: D018491:Dopamine Agonists; D018492:Dopamine Antagonists; D065127:Dopamine D2 Receptor Antagonists; D017448:Receptors, Dopamine D2; D011963:Receptors, GABA-A; D001971:Bromocriptine; D011333:Pro-Opiomelanocortin; D009074:Melanocyte-Stimulating Hormones; D006220:Haloperidol