[Effect of physostigmine on acetylcholine and monoamine metabolites in rat frontal cortex with lesions of the nucleus basalis of Meynert].

Acetylcholine (ACh) and monamine (MA) metabolites were collected from the frontal cortex of free moving rats, using a microdialysis technique. In rats subjected to bilateral ibotenic acid lesioning of the nucleus basalis of Meynert (nbM), ACh release was markedly decreased, while DOPAC, HVA and 5-HIAA were not affected. Physostigmine (0.3 mg/kg, IP) increased ACh concentration in the brain dialysate, and the rate of ACh increase was lower in nbM-lesioned rats than that in unoperated rats. Physostigmine also increased the concentration of MA metabolites in both nbM-lesioned and unoperated rats equally. The results indicate that there may be some interaction between non nbM-originated cholinergic systems and monoaminergic systems in the frontal cortex.