抄録
Objective: Effect of estrogen content on the development of delayed onset muscle soreness (DOMS) was examined in the ovariectomized rats. Methods: A total of 18 female rats [36 legs] were allocated to three groups. Control [CG, n=6], eccentric exercise [EEG, n=6] and exercise under ovariectomy [OVX, n=6]. Estrus cycle of each rat was determined by the smear test in blinded manner. These procedures were performed on the gastrocnemius [GS] muscle. Pain thresholds were measured daily by von Frey test [VFT] and Randall-Selitto test [RST] over the GS muscle for 1 week after the conditioning stimulation. Results: The thresholds of VFT and RST kept stable in the CG. during the experimental period, although the lowering of RST threshold was observed in the estrus period. In the EEG, the thresholds of RST of the exercised side were the lowest on the 1st day after exercise and returned on 7th day. No influence was observed in the contralateral side. In the OVX, however, the decrement of RST threshold of the exercised side was delayed and the lowest value was on the 2nd day after the exercise and returned on 7th day. The VFT thresholds were not changed significantly in the EEG and OVX. Conclusion: In the present study, the delay of development of muscular hyperalgesia was detected in the OVX rats. This result suggests that the change of estrogen content might to be a possible cause of muscle pain. [J Physiol Sci. 2007;57 Suppl:S112]
