WATERS, R.P.; PRINGLE, R.B.; SEMER, A.; KOCH, L.G.; BRITTON, S.L.; RENNER, K.J.; SWALLOW, J.G.; Univ. of South Dakota; Univ. of South Dakota; Univ. of South Dakota; Medical College of Ohio; Medical College of Ohio; Univ. of South Dakota; Univ. of South Dakota; : Monoaminergic Responses to Physical Activity in Female NIH Rats Bi-Directionally Selected for Endurance

Swallow and colleagues previously showed that voluntary activity and aerobic capacity are genetically correlated in house mice (Swallow et al. 1998). To further investigate this relationship we obtained NIH rats bi-directionally selected for aerobic treadmill running endurance. By generation eleven, these lines exhibited a 347% differential in intrinsic aerobic running capacity (Koch and Britton 2001). Animals were housed individually in clear Nalgene� cages with or without a 1 m running wheel. Wheel running activity and behavioral patterns were recorded for 8 weeks. High endurance rats ran 64% more than low lines, and spent 70% more time on the wheels than low lines. These results provide support for the hypothesis that voluntary activity and aerobic capacity are genetically correlated. Behavioral differences were also realized between the two lines, with the high line exhibiting lower levels of behaviors thought to be typical of anxiety (grooming and investigative). A number of clinical tests have also suggested that physical activity can ameliorate some of the symptoms associated with disorders such as anxiety and depression. These effects seem to be the result of changes in central monoaminergic activity. The striatum, amygdala, dorsal raphe, locus ceruleus and the hippocampus, are involved in anxiety and depression responses. We examined monoaminergic changes in these areas in response to exercise to assess the corollary mechanisms between physical activity, anxiety and depression. Monoamine analysis is in progress.