Effects of age and sex on the water maze performance and hippocampal cholinergic fibers in rats

We have examined if age-related deterioration of spatial memory and choline rgic innervation of the dentate gyrus is gender-specific. Aging progressive ly affected the performance of male and female rats in place discrimination version of the water maze task. On repeated acquisition task, only old mal es, but not old females, were significantly impaired relative to young and adult animals of both sexes. In parallel, we found that the age-associated reduction of the density of cholinergic fibers in the dentate gyrus was sig nificantly more profound in old males than in age-matched females. These re sults suggest that, although male and female rats have an identical pattern of reference memory decline, impairment of the working memory and deterior ation of the hippocampal cholinergic system are slower to develop in female s than in males. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved .