Frémont P, Riverin H, Frenette J, Rogers P A, Côté C
Muscle Biology Research Group, Laval University, Ste-Foy, Quebec, Canada.
Am J Physiol. 1991 Mar;260(3 Pt 2):R615-21. doi: 10.1152/ajpregu.1991.260.3.R615.
Carbonic anhydrase III (CA III; EC 4.2.1.1) is the most abundant cytosolic enzyme in type I skeletal muscle fibers. Methazolamide, a specific CA inhibitor, was used to characterize the effects of inhibiting CA III on the resistance to fatigue and recovery of the rat soleus muscle using a 60-min fatigue protocol performed in vitro at 25 degrees C. Incubation with 10(-3) M methazolamide resulted in a smaller decrease in tension production during the fatigue protocol, thereby increasing the total tension-time integral for the fatigue test. However, the rate and extent of recovery after the test were lower in the experimental group compared with the control group. A similar effect was observed at physiological temperature (35 degrees C). The results indicate that inhibition of CA III significantly influences tension production as early as 30 s into the stimulation protocol. Inhibition of CA III only during the recovery period did not influence the recovery profile, thereby indicating that the impaired recovery was related to the presence of methazolamide during the stimulation period.
碳酸酐酶III（CA III；EC 4.2.1.1）是I型骨骼肌纤维中最丰富的胞质酶。甲唑酰胺是一种特异性碳酸酐酶抑制剂，在25℃下体外进行60分钟疲劳实验，以此来表征抑制CA III对大鼠比目鱼肌疲劳抗性和恢复能力的影响。用10⁻³M甲唑酰胺孵育后，在疲劳实验过程中张力产生的下降幅度较小，从而增加了疲劳测试的总张力-时间积分。然而，与对照组相比，实验组测试后的恢复速率和恢复程度较低。在生理温度（35℃）下也观察到了类似的效果。结果表明，早在刺激实验开始30秒时，抑制CA III就会显著影响张力产生。仅在恢复期抑制CA III并不影响恢复情况，从而表明恢复受损与刺激期甲唑酰胺的存在有关。
