Quantitative in-situ hybridization histochemistry in the rat pituitary gland: effect of bromocriptine on prolactin and pro-opiomelanocortin gene expression.
The temporal effect of orally administered bromocriptine on pro-opiomelanocortin (POMC) and prolactin gene expression in male Sprague-Dawley rats was examined using in-situ hybridization histochemistry. Messenger RNA in the anterior and intermediate lobes could be clearly delineated in each section. Administration of bromocriptine resulted in a reduction in hybridization of 35S-labelled cDNA probe to prolactin mRNA from 0.69 x 10(12) to 0.29 x 10(12) copies bound/g after 150 h. POMC mRNA in the anterior lobe remained unchanged with 0.08 x 10(12) copies of probe bound/g for the duration of the experiment, while in the intermediate lobe it decreased from 2.44 x 10(12) to 0.44 x 10(12) copies of probe bound/g at 150 h. The rate of reduction in intermediate lobe POMC mRNA was similar to that of prolactin mRNA for the first 24 h but was subsequently more rapid and more profound, falling to 20% of the control value at 84 h and to 18% at 150 h.
Levy
A
A
Medical Unit, Charing Cross and Westminster Medical School, London.
Lightman
S L
SL
D000818:Animals; D001971:Bromocriptine / Q000494:pharmacology*; D005796:Genes / Q000187:drug effects*; D006651:Histocytochemistry; D008297:Male; D009693:Nucleic Acid Hybridization; D010902:Pituitary Gland / Q000032:analysis*; D011333:Pro-Opiomelanocortin / Q000235:genetics*; D011388:Prolactin / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains
D012333:RNA, Messenger; D001971:Bromocriptine; D011333:Pro-Opiomelanocortin; D011388:Prolactin