Plasma and pituitary thyroid-stimulating hormone levels in bromocriptine-treated New Zealand genetically hypertensive and normotensive rats.
1. The effects of a 13-day intraperitoneal (i.p.) infusion of bromocriptine, delivered by osmotic pump, on plasma and pituitary thyroid-stimulating hormone (TSH) levels were investigated in New Zealand genetically hypertensive (GH) rats and their normotensive (NT) controls. 2. In both the GH and NT rats, bromocriptine significantly reduced plasma TSH level but did not have any significant effect on pituitary TSH content. 3. No significant difference was found in the plasma TSH level and pituitary TSH content between the vehicle-treated GH and NT rats. 4. These results suggest that there are no differences between the GH and NT rats with regard to the activity of the central dopaminergic system influencing TSH release and also that TSH does not play a role in the hypertension of the GH rats.
Tan
B K
BK
Department of Pharmacology, Faculty of Medicine, National University of Singapore, Kent Ridge.
Hutchinson
J S
JS
D000818:Animals; D001971:Bromocriptine / Q000494:pharmacology*; D006973:Hypertension / Q000235:genetics / Q000378:metabolism*; D007260:Infusion Pumps; D008297:Male; D010902:Pituitary Gland / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D012016:Reference Values; D013972:Thyrotropin / Q000097:blood / Q000378:metabolism*
D001971:Bromocriptine; D013972:Thyrotropin