[3H]GBR 12935 binding in vivo in mouse brain: labelling of a piperazine acceptor site.
The binding of the selective dopamine uptake inhibitor [3H]GBR 12935 was studied in vivo in mouse brain. The binding was reversible with t1/2 = 80 min. The localisation of [3H]GBR 12935 binding and of dopaminergic receptors did not overlap. The binding of [3H]GBR 12935 was distributed almost uniformly throughout the brain. Also, the in vitro inhibition of dopamine uptake and the inhibition of in vivo [3H]GBR 12935 binding did not correlate when a series of relevant reference compounds was used. The potencies of various dopamine uptake inhibitors to induce stereotyped behavior did not correspond to the inhibitory potencies in the [3H]GBR 12935 binding assay. In conclusion, [3H]GBR 12935 labels in vivo a site which is different from the dopamine uptake complex. We have recently obtained results for the in vitro binding of [3H]GBR 12935 that indicate that this site could be a piperazine acceptor site.
Department of Pharmacology, Novo Industri A/S, Bagsvaerd, Denmark.
P H
PH
Andersen
J A
JA
Jansen
E B
EB
Nielsen
D000818:Animals; D001665:Binding Sites; D001921:Brain / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D004298:Dopamine / Q000378:metabolism; D007275:Injections, Intravenous; D008297:Male; D051379:Mice; D000077489:Piperazine; D010879:Piperazines / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013239:Stereotyped Behavior
D010879:Piperazines; D000077489:Piperazine; C044630:1-(2 (diphenylmethoxy)ethyl)-4-(3-phenylpropyl)piperazine; D004298:Dopamine