Dopaminergic projection to the central amygdala mediates the facilitatory effect of CCK-8US and caerulein on memory in rats.
The involvement of dopaminergic projection to the central amygdala in the facilitatory effect of cholecystokinin unsulphated octapeptide (CCK-8US) and caerulein (CER) on memory motivated affectively was investigated in male rats. CCK-8US and CER were administered subcutaneously at the doses of 10 micrograms kg-1and 0.5 microgram kg-1, respectively, immediately after a single learning trial in a passive avoidance situation, after bilateral 6-OHDA lesions to the central amygdala. Bilateral 6-OHDA lesions to the central amygdala totally abolished the facilitatory effect of CCK-8US and CER on retention of passive avoidance behaviour evaluated 24 h after the learning trial. These results may indicate that the facilitatory effect of CCK-8US and CER on memory motivated affectively is mediated by dopaminergic projection from ventral tegmental area to the central amygdala.
Winnicka
M M
MM
Department of Pharmacology, Medical University, Mickiewicza 2c, Białystok, 15-222, Poland.
Wiśniewski
K
K
D000679:Amygdala / Q000187:drug effects* / Q000502:physiology; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D002108:Ceruletide / Q000494:pharmacology*; D004298:Dopamine / Q000502:physiology*; D007279:Injections, Subcutaneous; D008297:Male; D008568:Memory / Q000187:drug effects*; D018697:Nootropic Agents / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D012844:Sincalide / Q000494:pharmacology*
D018697:Nootropic Agents; D002108:Ceruletide; D012844:Sincalide; D004298:Dopamine