Effects of infusions of the tyrosine kinase inhibitor radicicol into the hippocampus on short- and long-term memory of the inhibitory avoidance task

The aim of the present work was to test the role of protein tyrosine kinase s (PTKs) on both the short-term memory (STM) and long-term memory (LUND of the inhibitory avoidance task in rats using the inhibitor of tyrosine kinas e, radicicol. Rats implanted with cannulae in the CA1 area of the dorsal hi ppocampus received a 0.5 mul infusion of radicicol (0.5, 1, 5, 10, 20 mug/m l) or vehicle (water) at different times after training and were tested for STM (1.5 or 3 h) and LTM (24 h). Additionally, one group received radicico l 10 min prior to the test for LTM. Radicicol depressed both STM and LTM wh en infused before and immediately after training and had no effect on eithe r form of memory when infused 30 or 90 min after training. Radicicol also d epressed the retrieval of LTM. Our results indicate that memory formation a nd retrieval in the hippocampus can involve PTK activity, but the present f indings should be taken merely as a possible starting point for future inve stigations. (C) 2001 Lippincott Williams & Wilkins.