Exercise during pregnancy increases hippocampal brain-derived neurotrophic factor mRNA expression and spatial learning in neonatal rat pup

Physical activities for a few days can increase brain-derived neurotrophic factor (BDNF) mRNA in rat hippocampus. To investigate the influence of maternal exercise during pregnancy on rat pup hippocampal BDNF rnRNA, we studied its expression by a semi-quantitative RTPCR method after young. pregnant rats were exercised on a motor driven treadmill. Pups of exercised mothers had significantly increased hippocampal BDNF mRNA expression compared to the control rat pups at birth (on postnatal day 0) (P < 0.001). In contrast, hippocampal BDNF mRNA expression in pups of exercised mothers decreased significantly on postnatal day 28 (P < 0.002). Spatial learning of rat pups was examined by multiple T maze training for 7 consecutive days between postnatal days 40 and 47. Pups of exercised mothers showed a significant increase in spatial learning ability as demonstrated by significant decreases in total time from starting to target and total number of errors as compared to age-matched control pups during the first 4 days of 7 consecutive days on multiple T maze training (P < 0.05). Thus, physical exercise during gestation in pregnant mothers can increase hippocampal BDNF mRNA expression of postnatal pups and result in an improvement in spatial learning in pups from exercised dams. (C) 2003 Published by Elsevier Ireland Ltd.