title: Influence of cholecystokinin on the synaptosomal dopamine uptake in the nucleus accumbens of rats.
abstract: The influence of the sulfated cholecystokinin octapeptide (CCK-8S) on the synaptosomal high-affinity [(3)H]dopamine (DA) uptake was investigated in the medial and lateral part of nucleus accumbens in rats. CCK-8S induced a concentration-dependent biphasic inhibition of [(3)H]-DA uptake in both subregions. After preincubation of CCK-8S with the synaptosomes the inhibitory effect was completely abolished. Kinetic analysis of the uptake influence suggests an uncompetitive inhibition by CCK-8S; this means that CCK-8S attacks only the DA-uptake carrier complex by inhibitory manner. The possible regulatory relevance of this mechanism is discussed.
authors.affiliation: Institute of Medical Chemistry, University Medical School, 6701 Szeged POB 531, Hungary.
authors.forename: L
authors.initials: L
authors.lastname: Hetey
authors.forename: E
authors.initials: E
authors.lastname: Döring
authors.forename: B
authors.initials: B
authors.lastname: Penke