NICOTINE IMPROVES COGNITIVE DISTURBANCE IN SENESCENCE-ACCELERATED MICE

Senescence-accelerated mice (SAM), a murine model of age-related deter ioration in learning ability, were studied as to the acetylcholine (AC h) contents in the brain tissues and the effect of nicotine administra tion. We found that the ACh content of SAM-P/8 (accelerated senescence -prone) mice was lower than that of SAM-R/1 (accelerated senescence-re sistant) mice in the midbrain thalamus and the hypothalamus. In additi on, an IP administration of nicotine was found to improve learning abi lity of SAM-P/8 as shown by performance of a passive avoidance task. N icotine may potentiate cognitive function in SAM-P/8.