Interactions between anandamide-induced anterograde amnesia and post-training memory modulatory systems.
Rats were bilaterally implanted with indwelling cannulae in the CA1 region of the dorsal hippocampus. After recovery from surgery, they were trained in a one-trial, step-down inhibitory avoidance task using a 0.5 mA foot shock. The animals received intrahippocampal infusions of either vehicle or anandamide (100 microM, 0.5 microl/side) 30 min before training. Then, either immediately post-training or 3 h later, they received infusions of saline, noradrenaline (0.5 microg/side), SKF 38393 (1.5 microg/side), oxotremorine (0.6 microg/side) or Sp-cAMPs (0.5 microg/side) also in the hippocampus. All animals were tested for retention 24-h post-training. Anandamide produced anterograde amnesia. Immediate, but not delayed, post-training treatment with Sp-cAMPs and noradrenaline reversed this effect. SKF 38393 and oxotremorine had no influence on the amnesia caused by anandamide either when given immediately or 3 h after training. The results suggest that the amnesic effect of anandamide is related to the known noradrenergic regulation of cAMP-dependent protein kinase (PKA) activity previously described in the hippocampus immediately after avoidance training, which is crucial to long-term memory (LTM) formation.
Barros
Daniela Martí
DM
Laboratório de Comportamento, Departamento de Ciências Fisiológicas, CENPRE, Fundação Universidade Federal do Rio Grande, Av Itália Km 8, 96201-900 Rio Grande, RS, Brazil. dani@octopus.furg.br
Carlis
Vania
V
Maidana
Michelle
M
Silva
Eli Sinnott
ES
Baisch
Ana Luiza Muccillo
AL
Ramirez
Maria Rosana
MR
Izquierdo
Iván
I
D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine / Q000494:pharmacology; D020324:Amnesia, Anterograde / Q000139:chemically induced / Q000503:physiopathology*; D000818:Animals; D001095:Arachidonic Acids; D001362:Avoidance Learning / Q000187:drug effects; D001522:Behavior, Animal; D002121:Calcium Channel Blockers; D016009:Chi-Square Distribution; D000242:Cyclic AMP / Q000031:analogs & derivatives* / Q000494:pharmacology; D018491:Dopamine Agonists / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D063388:Endocannabinoids; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects / Q000503:physiopathology; D008568:Memory / Q000502:physiology*; D009020:Morphine / Q000494:pharmacology; D018721:Muscarinic Agonists / Q000494:pharmacology; D009294:Narcotics / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology; D010095:Oxotremorine / Q000494:pharmacology; D053284:Polyunsaturated Alkamides; D051381:Rats; D017208:Rats, Wistar; D011930:Reaction Time / Q000187:drug effects; D013873:Thionucleotides / Q000494:pharmacology
D001095:Arachidonic Acids; D002121:Calcium Channel Blockers; D018491:Dopamine Agonists; D063388:Endocannabinoids; D004791:Enzyme Inhibitors; D018721:Muscarinic Agonists; D009294:Narcotics; D053284:Polyunsaturated Alkamides; D013873:Thionucleotides; C016957:adenosine-3',5'-cyclic phosphorothioate; D010095:Oxotremorine; D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D009020:Morphine; D000242:Cyclic AMP; C078814:anandamide; D009638:Norepinephrine