Influence of histamine depletion on learning and memory recollection in rats

Abstract

To clarify the role of endogenous histamine in learning and memory, the effect of α-fluoromethylhistidine on active avoidance response in rats was studied. α-Fluoromethylhistidine (20–100 mg/kg or 10–50 µg) significantly (PPPP<0.01) decreased the brain histamine content, especially in the hippocampus and hypothalamus. When α-fluoromethylhistidine (50 µg) was injected intracerebroventricularly, there is a high correlation between a prolongation of the response latency and a decrease in histamine content of these brain areas. Based on these findings, it was concluded that an intimate relation may exist between a prolongation of response latency in the active avoidance response and a decrease in the brain histamine content; endogenous histamine may play an important role in learning and memory recollection in rats.