Microdialysis measurement of acetylcholine in rat hippocampus during severe insulin-induced hypoglycemia.

OBJECTIVE: It has been well acknowledged that hypoglycemia induces cognitive impairment. However, the behavior of hippocampal cholinergic system, which is thought to play a key role in cognition, during hypoglycemia remains to be elucidated.

MATERIALS AND METHODS: In this study we conducted a microdialysis using 9 weeks old virgin male Wistar/ST rats to determine the changes of extracelluar acethylcholine and glucose levels in the hippocampus during insulin-induced severe hypoglycemia, and compared the results with those obtained from a microdialysis in the striatum.

RESULTS: The extracelluar concentrations of acethylcholine both in the hippocampus and striatum did not change during hypoglycemia.

CONCLUSION: The results of the present study may suggest that changes of hippocampal cholinergic release may not be involved in the mechanism of cognitive impairment during hypoglycemia.