Uncoupling of in vivo torque production from EMG in mouse muscles injured by eccentric contractions

被引:78
作者
Warren, GL [1 ]
Ingalls, CP [1 ]
Shah, SJ [1 ]
Armstrong, RB [1 ]
机构
[1] Texas A&M Univ, Muscle Biol Lab, College Stn, TX 77843 USA
来源
JOURNAL OF PHYSIOLOGY-LONDON | 1999年 / 515卷 / 02期
关键词
D O I
10.1111/j.1469-7793.1999.609ac.x
中图分类号
Q189 [神经科学];
学科分类号
071006 ;
摘要
1. The main objective of this study was to determine whether eccentric contraction-induced muscle injury causes impaired plasmalemmal action potential conduction, which could explain the injury-induced excitation-contraction coupling failure. Mice were chronically implanted with stimulating electrodes on the left common peroneal nerve and with electromyographic (EMG) electrodes on the left tibialis anterior (TA) muscle. The left anterior crural muscles of anaesthetized mice were stimulated to perform 150 eccentric (ECC) (n = 12 mice) or 150 concentric (CON) (n = 11 mice) contractions. Isometric torque, EMG root mean square (RMS) and M-wave mean and median frequencies were measured before, immediately after, and at 1, 3, 5 and 14 days after the protocols. In parallel experiments, nicotinic acetylcholine receptor (AChR) concentration was measured in TA muscles to determine whether the excitation failure elicited a denervation-like response. 2. Immediately after the ECC protocol, torque was reduced by 47-89%, while RMS was reduced by 9-21%; the RMS decrement was not different from that observed for the CON protocol, which did not elicit large torque deficits. One day later, both ECC and CON RMS had returned to baseline values and did not change over the next 2 weeks. However, torque production by the ECC group showed a slow recovery over that time and was still depressed by 12-30% after 2 weeks. M-wave mean and median frequencies were not affected by performance of either protocol. 3. AChR concentration was elevated by 79 and 368% at 3 and 5 days, respectively, after the ECC protocol; AChR concentration had returned to control levels 2 weeks after the protocol. Bt the time of peak AChR concentration in the ECC protocol muscles (i.e. 5 days), AChR concentration in CON protocol muscles was not different from the control level. 4. In conclusion, these data demonstrate no major role for impaired plasmalemmal action potential conduction in the excitation-contraction coupling failure induced by eccentric contractions. Additionally, a muscle injured by eccentric contractions shows a response in AChR concentration similar to a transiently denervated muscle.
引用
收藏
页码:609 / 619
页数:11
相关论文
共 30 条
[1]  
Adams L, 1998, J NEUROBIOL, V35, P245, DOI 10.1002/(SICI)1097-4695(19980605)35:3<245::AID-NEU2>3.0.CO
[2]  
2-Z
[3]   CHOLINERGIC SITES IN SKELETAL-MUSCLE .1. DENERVATION EFFECTS [J].
ALMON, RR ;
APPEL, SH .
BIOCHEMISTRY, 1976, 15 (17) :3662-3667
[4]   INTRACELLULAR CALCIUM AND FORCE IN SINGLE-MOUSE MUSCLE-FIBERS FOLLOWING REPEATED CONTRACTIONS WITH STRETCH [J].
BALNAVE, CD ;
ALLEN, DG .
JOURNAL OF PHYSIOLOGY-LONDON, 1995, 488 (01) :25-36
[5]  
Basmajian JV, 1985, MUSCLE ALIVE THEIR F, P42
[6]   MUSCLE SORENESS AND SERUM CREATINE-KINASE ACTIVITY FOLLOWING ISOMETRIC, ECCENTRIC, AND CONCENTRIC EXERCISE [J].
CLARKSON, PM ;
BYRNES, WC ;
MCCORMICK, KM ;
TURCOTTE, LP ;
WHITE, JS .
INTERNATIONAL JOURNAL OF SPORTS MEDICINE, 1986, 7 (03) :152-155
[7]   CONTROL OF ACETYLCHOLINE RECEPTORS IN SKELETAL-MUSCLE [J].
FAMBROUGH, DM .
PHYSIOLOGICAL REVIEWS, 1979, 59 (01) :165-227
[8]   The tubular vacuolation process in amphibian skeletal muscle [J].
Fraser, JA ;
Skepper, JN ;
Hockaday, AR ;
Huang, CLH .
JOURNAL OF MUSCLE RESEARCH AND CELL MOTILITY, 1998, 19 (06) :613-629
[9]   MYOFIBRILLAR DAMAGE FOLLOWING INTENSE ECCENTRIC EXERCISE IN MAN [J].
FRIDEN, J ;
SJOSTROM, M ;
EKBLOM, B .
INTERNATIONAL JOURNAL OF SPORTS MEDICINE, 1983, 4 (03) :170-176
[10]  
Fuglevand AJ, 1995, ADV EXP MED BIOL, V384, P101