EFFECT OF TOOTH LOSS ON SPATIAL-LEARNING AND MEMORY ABILITIES IN ADULT-RATS - IMPLICATIONS FOR CENTRAL ACETYLCHOLINE

The effect of tooth loss on the learning and memory abilities in spatial memory learning was investigated in adult rats. Twenty male Wistar rats (3 months old) were divided into two groups. The molars were extracted from ten rats under generalanesthesia and the remaining ten were anesthetized as controls. The learning and memory abilities in both groups were comparatively tested in habituation learning, water maze and radial maze tasks on 3 months after extraction. The learning and memory tended to be impaired in the tooth-extracted group. In the habituation learning task the rate of decrease in movement count was lower in the tooth-extracted group compared to the control group, and in the radial maze task the frequency of error increased and that of initial correct response decreased in the tooth-extracted group compared to the control group. The results suggest that the loss of teeth may affect the learning and memory abilities in adult rats.