Influence of acute and chronic treadmill exercise on rat brain POMC gene expression

JIAXU, C., and Y. WEIYI. Influence of acute and chronic treadmill exercise on rat brain POMC gene expression. Med. Sci. Sports Exerc., Vol. 32, No. 5, pp. 954–957, 2000. Methods In situ hybridization using biotin-labeled POMC cRNA probes and integrated image pattern analysis were used to observe the effect of chronic (total 7 wk) and acute treadmill exercise (an initial speed of 15 m·min−1 gradually increased to 35 m·min−1 with 0°, 20–25 min·d−1 duration) on the changes of POMC mRNA expression in different areas of the rat brain. Results Acute exercise performed after 7 wk of training resulted in a decrease in the expression of POMC mRNA in both the frontal cortex and hippocampal CA1 of the experimental rats. Three hours postexercise, the POMC mRNA indicator had not yet returned to normal expression levels in the frontal cortex, but hippocampal CA1 levels showed increases above normal levels 30 min postexercise. Expression levels in the hypothalamus were shown to be increased immediately after acute exercise and remained high even during remeasurement 3 h postexercise. Conclusion Changes in POMC gene expression in response to chronic and high-intensity acute exercise vary depending on the brain region examined.