INTERACTIONS BETWEEN ANANDAMIDE-INDUCED ANTEROGRADE AMNESIA AND POST-TRAINING MEMORY MODULATORY SYSTEMS.

BARROS DM, CARLIS V, MAIDANA M, SILVA ES, BAISCH AL, RAMIREZ MR, IZQUIERDO I.

BRAIN RESEARCH

ELSEVIER SCIENCE BV

Año: 2004 vol. 30 p. 66 - 71

0006-8993

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-bidi-font-family:"Times New Roman"; mso-ansi-language:PT-BR; mso-fareast-language:PT-BR; mso-bidi-language:AR-SA;} @page Section1 {size:595.3pt 841.9pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:35.4pt; mso-footer-margin:35.4pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> 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 AM, 0.5 Al/side) 30 min before training. Then, either immediately post-training or 3 h later, they received infusions of saline, noradrenaline (0.5 Ag/side), SKF 38393 (1.5 Ag/side), oxotremorine (0.6 Ag/side) or Sp-cAMPs (0.5 Ag/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.