Previous Hyperthermic Treatment Increases Mitochondria Oxidative Enzyme Activity and Exercise Capacity in Rats

熱休克前處置增加大白鼠之粒腺體中氧化性酵素的活性及延長持續運動之能力

陳香文(Hsiang-Wen Chen) ； 陳世杰(Shih-Chieh Chen) ； 蔡錦蓮(Jin-Lian Tsai) ； 楊瑞成(Rei-Cheng Yang)

《The Kaohsiung Journal of Medical Sciences》 15卷10期 (1999/10) Pp. 572-580

https://doi.org/10.6452/KJMS.199910.0572

摘要

The study was designed to investigate the role of hyperthermia in the tolerance of exercise in rats and theposible mechanism was examined. The hyperthermic pretreatment was performed using an electric pad on the anesthesized rats 24 hours before exercise. at were exercised passively in a motor-controlled round treadmill in high temperature environment (36-37°C) until exhaustion. The capacity of tolerance was calculated. Lymphocytes and gastrocnemius muscle were collected from both groups. The changes in muscular morphology, mitochondria oxidative enzyme activity and induction of Hsp72 were investigated. The results revealed that experimental rats were more tolerant to exercise at high temperature than the control group; the duration time were 89 ± 17.8 mim and 63.1 ± 7.3 mim, respectively. Hsp72 was induced markedly in the experimental group, both in muscle and lymphocytes, indicating a heat shock response. There was no significant change in morphology of the mitochodria, 24 hours after hyperthermic treatment, as shown by histopathological and electromicroscopic investigation. However, the activity of mitochondrial enzymes increased significantly in experimental group before exercise:
84.6 ± 6.3 and 345 ± 15.4 (nmole cytochrome c/mm/mg total protein) respectively of NADH-cytochome c reductase and succinate-cytochome c reductase activity in experimental group compared to 58.9 ± 4.7 and 269.0 ± 24.0 in control group (p ＜0.05, by student t-test). It is concluded that hyperthermic treatment enhances muscular mitochondrial oxidative enzyme activity in rats, and results in increasing tolerance to exercise at high temperature. The heat shock response, most probably the inducible Hsp72, is a crucial factor in this effect.

並列摘要

The study was designed to investigate the role of hyperthermia in the tolerance of exercise in rats and theposible mechanism was examined. The hyperthermic pretreatment was performed using an electric pad on the anesthesized rats 24 hours before exercise. at were exercised passively in a motor-controlled round treadmill in high temperature environment (36-37°C) until exhaustion. The capacity of tolerance was calculated. Lymphocytes and gastrocnemius muscle were collected from both groups. The changes in muscular morphology, mitochondria oxidative enzyme activity and induction of Hsp72 were investigated. The results revealed that experimental rats were more tolerant to exercise at high temperature than the control group; the duration time were 89 ± 17.8 mim and 63.1 ± 7.3 mim, respectively. Hsp72 was induced markedly in the experimental group, both in muscle and lymphocytes, indicating a heat shock response. There was no significant change in morphology of the mitochodria, 24 hours after hyperthermic treatment, as shown by histopathological and electromicroscopic investigation. However, the activity of mitochondrial enzymes increased significantly in experimental group before exercise:
84.6 ± 6.3 and 345 ± 15.4 (nmole cytochrome c/mm/mg total protein) respectively of NADH-cytochome c reductase and succinate-cytochome c reductase activity in experimental group compared to 58.9 ± 4.7 and 269.0 ± 24.0 in control group (p ＜0.05, by student t-test). It is concluded that hyperthermic treatment enhances muscular mitochondrial oxidative enzyme activity in rats, and results in increasing tolerance to exercise at high temperature. The heat shock response, most probably the inducible Hsp72, is a crucial factor in this effect.

並列關鍵字

tolerance ； heat shock proteins ； mitochondrial enzyme activity