Insulin selectively downregulates alpha2-adrenoceptors in the arcuate and dorsomedial nucleus.
Intracerebroventricular infusion of insulin (2 mU/ day) produced selective downregulation of 3H-paraminoclonidine binding to alpha2-adrenoceptors in the hypothalamic arcuate (14%) and dorsomedial (19%) nuclei out of 16 forebrain areas in Wistar rats. Binding of 3H-prazosin to alpha1-adrenoceptors was unaffected. This is in keeping with the known effect of insulin on catecholamine and neuropeptide Y metabolism in these brain regions that play an important role in energy homeostasis.
Levin
B E
BE
Neurology Service (127 C), DVA Medical Center, E. Orange, NJ 07018, USA.
Israel
P
P
Lattemann
D P
DP
D058669:Adrenergic alpha-2 Receptor Antagonists; D000679:Amygdala / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000187:drug effects / Q000378:metabolism*; D001345:Autoradiography; D004302:Dorsomedial Hypothalamic Nucleus / Q000187:drug effects / Q000378:metabolism*; D015536:Down-Regulation / Q000187:drug effects*; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism; D007276:Injections, Intraventricular; D007328:Insulin / Q000494:pharmacology*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D018341:Receptors, Adrenergic, alpha-2 / Q000096:biosynthesis*; D013788:Thalamus / Q000187:drug effects / Q000378:metabolism
D058669:Adrenergic alpha-2 Receptor Antagonists; D007004:Hypoglycemic Agents; D007328:Insulin; D018341:Receptors, Adrenergic, alpha-2