A role for hippocampal gastrin-releasing peptide receptors in extinction of aversive memory.
Although the gastrin-releasing peptide receptor has been implicated in memory consolidation, previous studies have not examined whether it is involved in extinction. Here we show that gastrin-releasing peptide receptor blockade in the hippocampus disrupts extinction of aversive memory. Male rats were trained in inhibitory avoidance conditioning and then returned repeatedly to the training context without shock on a daily basis for 3 days. Infusion of a gastrin-releasing peptide receptor antagonist or the protein synthesis inhibitor anisomycin into the dorsal hippocampus immediately after the first extinction session blocked extinction. These drugs did not affect performance in subsequent sessions when the first extinction session (1 day after training) was omitted. The results indicate that hippocampal gastrin-releasing peptide receptors are involved in memory extinction.
Luft
Tatiana
T
Cellular and Molecular Neuropharmacology Research Group, Department of Pharmacology, Institute for Basic Health Sciences, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
Flores
Debora G
DG
Vianna
Monica R M
MR
Schwartsmann
Gilberto
G
Roesler
Rafael
R
Izquierdo
Ivan
I
D000818:Animals; D000841:Anisomycin / Q000494:pharmacology; D001362:Avoidance Learning / Q000187:drug effects / Q000502:physiology*; D001522:Behavior, Animal; D001839:Bombesin / Q000031:analogs & derivatives / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005108:Extinction, Psychological / Q000187:drug effects / Q000502:physiology*; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D008297:Male; D008568:Memory / Q000187:drug effects / Q000502:physiology*; D010446:Peptide Fragments / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D011930:Reaction Time / Q000187:drug effects; D018004:Receptors, Bombesin / Q000037:antagonists & inhibitors / Q000502:physiology*; D018709:Statistics, Nonparametric; D013997:Time Factors
D004791:Enzyme Inhibitors; D010446:Peptide Fragments; D018004:Receptors, Bombesin; C071363:bombesin (6-14), Tpi(6)-Leu(13)-psi(CH2NH)-Leu(14)-; D000841:Anisomycin; D001839:Bombesin