Abstract
Effects of the intracerebroventricular administration of 1-[[[5-(4-nitrophenyl)-2-furanyl]methylene]imino]-2-, 4-imidazolidinedione (dantrolene, an inhibitor of intracellular Ca2+ mobilization) on learning/memory were investigated in mice using step-through passive avoidance and radial-arm maze tests. In the passive avoidance test, the administration of 6 nmol of dantrolene shortened the response latency in the retention test. The number of times of acquisition training required to achieve the criterion latency (300 s) did not change in the acquisition test. Ten nmol of administration of dantrolene increased the number of times of acquisition training required to achieve the criterion latency in the acquisition test and shortened the response latency in the retention test. In the radial-arm maze tests, 20 nmol of administration of dantrolene disrupted maze-choice accuracy and increased error numbers. These results suggest that intraneuronal Ca2+ mobilization plays important roles in learning and memory.