OBJECTIVETo explore the delayed protection of exercise preconditioning from the relative myocardial ischemia-reperfusion injury.

METHODSThe experiment included the vivo experiment and the vitro experiment, 32 Wistar rats in each experiment were divided into 4 groups randomly: control group (CN), relative ischemia reperfusion group (IR), exercise preconditioning group (EP) and Exercise preconditioning + relative ischemia-reperfusion group (EI). We detected the third loading exercise time, the levels of MDA in serum in vivo experiment and the Cardiac function parameter, the levels of MDA in coronary effluent in vitro experiment.

RESULTS(1) The vivo experiment: The third loading exercise time of EI group [(71.67 +/- 9.00) min] increased significantly compared with that of IR group [(58.67 +/- 4.13) min] (P < 0.05); The levels of MDA in serum of EP group (107.00 +/- 35.99) micromol/L and EI group [(152.23 +/- 29.94) micromol/L] decreased significantly contrasted to IR group (313.20 +/- 43.40 micromol/L) (P < 0.05). (2) The vitro experiment: The PRP (heart rate * left ventricular developed pressure) in reperfusion period of CN group and EP group were stable relatively, while it reached the peak after 30 minutes and almost recovered to the level before ischemia in EI group. The parameter of IR group recovered slightly but was lower significantly than that before ischemia. There was significant difference between the recovery rate of Cardiac function of EI group and that of IR group. The increase of MDA in coronary effluent after Ischemia-reperfusion of EP group (0.34 +/- 0.24 micromol/L) and EI group [(0.41 +/- 0.26) micromol/L] decreased significantly contrasted to that of IR group [(1.27 +/- 0.52) micromol/L] (P < 0.05).

CONCLUSIONEP has the obvious delayed protection from the relative myocardial ischemia-reperfusion injury.

This article presents the design of a treadmill of comprehensive training experiment for rats. The treadmill is composed of six tracks and two of them were designed as conventional plane, two were designed to swing right and left, and two were designed to swing back and forth. The power was provided by six motors. The MSP430F149 is used as core to adjust the swing rate and the grade of electric shock. The IAR for MSP430 is used to design the software. The speed of the six tracks could be adjusted between 0 and 30 m/min. The swing tracks of back and forth can be swung for 3-25 times per minute and the swing tracks of right and left for 3-32 times. The electric shock can be divided into three levels, i. e. strong, middle, and weak level for each track. The digital comprehensive training treadmill can meet different training needs, and provide experimental data for mechanism research of some related diseases.
Animals ; Equipment Design ; Exercise Test ; instrumentation ; Physical Conditioning, Animal ; instrumentation ; Rats

OBJECTIVETo reveal the effects of three days' repeated exhausted eccentric exercise on the skeletal muscle apoptosis and proliferation in rats.

METHODSFifty male SD rats aged at 8 week old were randomly divided into control group (C) and training groups (B1, B2, B3, B4) (n = 10), the training groups ran on a treadmill every day till exhausted. After they had been trained repeatedly for three days, their medial head of triceps brachii muscle cell apoptosis was detected in paraffin section by the TUNEL, expression of proliferating cell nuclear antigen (PCNA) protein was examined by immunohistochemistry.

RESULTS(1) The apoptosis appeared sequential change, and it was consistent with the exercise-induced skeletal muscle micro-injury (EIMmI). The apoptosis index in the training group after exercise was much greater than that in the control group (P < 0.05), and it reached the peak at 24 h after exercise, then it reduced at 48 h after exercise. (2) The express of PCNA exhibited a sequential change after exercise, the proliferation index in the training group after exercise was greater than that in the control group (P < 0.05), it increased after exercise immediately, but it reduced at 3 h after exercise, then was reached the peak at 24 h after exercise, the proliferation index was moderately correlated with the apoptosis index (P < 0.05).

CONCLUSION(1) Cell apoptosis can induce the delayed skeletal muscle damage. (2) Apoptosis may be a start factor of skeletal muscle regeneration.

Animals ; Gene Expression ; Insulin Resistance ; Male ; Physical Conditioning, Animal ; Rats ; Rats, Sprague-Dawley ; Receptors, Adiponectin ; genetics

Animals ; Calreticulin ; metabolism ; Male ; Muscle, Skeletal ; metabolism ; Oxidative Stress ; Physical Conditioning, Animal ; Rats ; Rats, Sprague-Dawley

Animals ; Drugs, Chinese Herbal ; pharmacology ; Hematopoietic System ; drug effects ; Male ; Physical Conditioning, Animal ; Rats ; Rats, Wistar

Animals ; Blood Glucose ; Diet, High-Fat ; Ghrelin ; blood ; Lipids ; blood ; Physical Conditioning, Animal ; Rats

Animals ; Cardiovascular System ; physiopathology ; Fatigue ; drug therapy ; Mice ; Oxidative Stress ; Periplaneta ; chemistry ; Physical Conditioning, Animal

Animals ; Diet ; Fatty Acids, Monounsaturated ; administration & dosage ; Insulin Resistance ; Physical Conditioning, Animal ; Rats

Animals ; Antioxidants ; metabolism ; Diabetes Mellitus, Experimental ; metabolism ; Melatonin ; metabolism ; Physical Conditioning, Animal ; Rats