Intra CA1 insulin microinjection improves memory consolidation and retrieval.

Although the brain was considered as an insulin-insensitive organ, recent studies have shown that insulin receptors exist in the brain and insulin modulates some of the brain tasks. Insulin and its receptor are found in specific areas of CNS with a variety of region-specific functions different from its direct glucose regulation in the periphery. The hippocampus and cerebral cortex distributed insulin/insulin receptor has been shown to be involved in brain cognitive functions. The improving effect of insulin on spatial memory acquisition has been shown. In the present study, the effect of insulin microinjection into the CA1 region of rat hippocampus on spatial memory consolidation and retrieval has been investigated. Insulin in 12 MU (but not in 0.5 and 6 MU) improved both memory retrieval and consolidation.