Data/hora: 17/06/2024 14:52:12

Provedor de dados: | Brazilian Journal of Medical and Biological Research
País: | Brazil
Título: | Agents that affect cAMP levels or protein kinase A activity modulate memory consolidation when injected into rat hippocampus but not amygdala
Autores: | Bevilaqua,L.; Ardenghi,P.; Schröder,N.; Bromberg,E.; Quevedo,J.; Schmitz,P.K.; Bianchin,M.; Walz,R.; Schaeffer,E.; Medina,J.H.; Izquierdo,I.
Data: | 1997-08-01
Ano: | 1997
Palavras-chave: | Memory formation; Memory modulation; Hippocampus; Amygdala; CAMP/PKA/CREB-P pathway; Dopamine D; Receptors; SS-adrenoceptors; 5HT1A receptors.
Resumo: | Male Wistar rats were trained in one-trial step-down inhibitory avoidance using a 0.4-mA footshock. At various times after training (0, 1.5, 3, 6 and 9 h for the animals implanted into the CA1 region of the hippocampus; 0 and 3 h for those implanted into the amygdala), these animals received microinfusions of SKF38393 (7.5 µg/side), SCH23390 (0.5 µg/side), norepinephrine (0.3 µg/side), timolol (0.3 µg/side), 8-OH-DPAT (2.5 µg/side), NAN-190 (2.5 µg/side), forskolin (0.5 µg/side), KT5720 (0.5 µg/side) or 8-Br-cAMP (1.25 µg/side). Rats were tested for retention 24 h after training. When given into the hippocampus 0 h post-training, norepinephrine enhanced memory whereas KT5720 was amnestic. When given 1.5 h after training, all treatments were ineffective. When given 3 or 6 h post-training, 8-Br-cAMP, forskolin, SKF38393, norepinephrine and NAN-190 caused memory facilitation, while KT5720, SCH23390, timolol and 8-OH-DPAT caused retrograde amnesia. Again, at 9 h after training, all treatments were ineffective. When given into the amygdala, norepinephrine caused retrograde facilitation at 0 h after training. The other drugs infused into the amygdala did not cause any significant effect. These data suggest that in the hippocampus, but not in the amygdala, a cAMP/protein kinase A pathway is involved in memory consolidation at 3 and 6 h after training, which is regulated by D1, ß, and 5HT1A receptors. This correlates with data on increased post-training cAMP levels and a dual peak of protein kinase A activity and CREB-P levels (at 0 and 3-6 h) in rat hippocampus after training in this task. These results suggest that the hippocampus, but not the amygdala, is involved in long-term storage of step-down inhibitory avoidance in the rat.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000800009
Editor: | Associação Brasileira de Divulgação Científica
Relação: | 10.1590/S0100-879X1997000800009
Formato: | text/html
Fonte: | Brazilian Journal of Medical and Biological Research  v.30 n.8 1997
Fonte: | info:eu-repo/semantics/openAccess