Changes of High-Affinity Choline Uptake in the Hippocampus of Old Rats after Long-Term Administration of Two Nootropic Drugs (Tacrine and Ginkgo biloba Extract)

Abstract

The effect of tacrine (THA), the cholinesterase inhibitor, and Ginkgo biloba extract (EGb) on the sodium-dependent high-affinity choline uptake (HACU) into hippocampal synaptosomes was studies in vivo in model experiments after long-term administration in old rats (THA 5 or 10 mg/kg/day p.o. for 3 months; EGb 50 or 100 mg/kg/day p.o. for 30 days) and in vitro tests. EGb increased HACU both in vivo and in vitro experiments. On the contrary, THA induced a decrease of HACU under both conditions, suggesting a negative impact on the cholinergic neuronal activity.