Intraventricular 6-hydroxydopamine increases thyrotropin-releasing hormone (TRH) content in regions of rat brain.
Rats were given intraventricular (ivt) injections of various doses (50-400 micrograms, hydrobromide salt) of 6-hydroxydopamine (6-OHDA) and killed 1, 3 or 6 days later. Brains were removed, dissected into 11 regions, and the thyrotropin-releasing hormone (TRH) content of each region was measured by radioimmunoassay. 6-OHDA (400 micrograms) caused significant elevations in the TRH content of 6 regions: olfactory bulb, anterior cortex, brainstem, posterior cortex, hippocampus, and amygdala-piriform cortex. The magnitude of these increases ranged from 59% in olfactory bulb to 497% in hippocampus and was, in all cases, greatest at 3 days. These results suggest that the TRH content of certain brain regions may be regulated by catecholamine neurotransmitters.
D000818:Animals; D001679:Biogenic Amines / Q000378:metabolism; D001923:Brain Chemistry / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006892:Hydroxydopamines / Q000494:pharmacology*; D007276:Injections, Intraventricular; D008297:Male; D016627:Oxidopamine; D051381:Rats; D011919:Rats, Inbred Strains; D013973:Thyrotropin-Releasing Hormone / Q000378:metabolism*; D013997:Time Factors
D001679:Biogenic Amines; D006892:Hydroxydopamines; D013973:Thyrotropin-Releasing Hormone; D016627:Oxidopamine