Sign up for email alert when new content gets added: Sign up
Mihoko Tomida
Matsumoto Dental University, Japan
Posters & Accepted Abstracts: J Current Res: Int Medicine
Introduction: It is reported that excessive sports increase �²-endorphin in the serum, but there are few reports about the expression of the opioid in the brain. Therefore, we investigate a change of �²-endorphin secreted in the rat brain after exercise. Method: With male Wistar rats, we investigated the expression of �²-endorphin in the periaqueductal gray (DM: Dorsomedial, DL: Dorsolateral, L: Lateral, VL: Ventrolateral) immune histologically. The conditions are control group (only in a rota-rod treadmill), high-speed exercise group (11 m/min), low-speed exercise group (6.6 m/min). They exercise twice a day 7 days for 30 minutes. After 7 days, the corticosterone density in the rat blood was measured. The brain tissue of 20 �¼m was immune stained by the free-floating method using an antibody of �²-endorphin. Immuno-stained section was photographed by a digital camera and immno positive amount in a square of 100 �¼m was determined by using software. Result: The median of corticosterone density was control group 294 �¼g/ml, high-speed group 349 �¼g/ml and low-speed group 345 �¼g/ml. The significant difference was recognized between control and both exercise group. The median of endorphin expression in the periaqueductal gray is 27.9 �¼m2, 51.0 �¼m2, 23.5 �¼m2. The significant difference was recognized between high-speed group and low-speed group or control group. By the part distinction, the expression of �²-endorphin in DM and DL increase in particular when rats ran in high-speed. Conclusion: The present findings suggest that stress after exercise in the rata-rod treadmill might increase regardless of the speed. However, the sedative effect is strong at vigorous exercise.
E-mail:
mtomi@po.mdu.ac.jp