Antagonism of cholecystokinin function in the rostral and caudal nucleus accumbens: differential effects on brain stimulation reward.
Microinjections of proglumide, a cholecystokinin (CCK) receptor antagonist, into the rostral and caudal nucleus accumbens (NA) were examined for effects on intracranial self-stimulation (ICSS) derived from the ventral tegmental area (VTA). Proglumide was found to dose-dependently antagonize ICSS when administered in the caudal NA but had weak facilitatory effects when administered in the rostral NA. These findings were interpreted to suggest that endogenous CCK is involved in the neurochemical mechanisms underlying brain stimulation reward derived from the VTA. The present results are consistent with the notion that caudal NA CCK function is associated with facilitatory influences on brain stimulation reward. The dopamine antagonist-like effects of CCK appear to involve CCK actions in the more rostral regions of the NA and may reflect the contribution of non-dopamine neuron-derived source(s) of CCK.
Vaccarino
F J
FJ
Department of Psychology, University of Toronto, Ont., Canada.
Vaccarino
A L
AL
D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D002766:Cholecystokinin / Q000502:physiology*; D005973:Glutamine / Q000031:analogs & derivatives*; D008297:Male; D009714:Nucleus Accumbens / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D011377:Proglumide / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011949:Receptors, Cholecystokinin / Q000187:drug effects; D012201:Reward / Q000502:physiology*; D012686:Septal Nuclei / Q000502:physiology*
D011949:Receptors, Cholecystokinin; D005973:Glutamine; D002766:Cholecystokinin; D011377:Proglumide