de Haan A, Koudijs J C, Wevers R A, Wieringa B
Faculty of Human Movement Sciences, Vrije Universiteit, Amsterdam, The Netherlands.
Exp Physiol. 1995 May;80(3):491-4. doi: 10.1113/expphysiol.1995.sp003863.
Twitch force production was normal in muscles of mice which lack MM-creatine kinase, but the tetanic force:twitch force ratio was lower than in control muscles (3.60 vs 4.27; P < 0.05). In a series of repeated tetanic contractions the force in the second contraction was already markedly depressed (20-50%), while subsequently only small changes were observed. The effect was greater in exercise that would require a higher metabolic peak flux. The depressed force production was not accompanied by a slowing of relaxation, indicating that enough ATP was present to sustain myofibrillar ATPase and Ca(2+)-ATPase activity.
缺乏MM-肌酸激酶的小鼠肌肉的单收缩力产生正常，但强直收缩力与单收缩力之比低于对照肌肉（3.60对4.27；P<0.05）。在一系列重复的强直收缩中，第二次收缩时的力量已明显降低（20%-50%），而随后仅观察到微小变化。在需要更高代谢峰值通量的运动中，这种效应更大。力量产生的降低并未伴随着舒张减慢，这表明存在足够的ATP来维持肌原纤维ATP酶和Ca(2+)-ATP酶的活性。
