The effect of a period of aerobic exercise with inhibition of nitric oxide on the fast and slow twitch muscle fibers neurotrypsin levels in elderly male rats

One of the causes of neuromuscular junction (NMJ) disruption in old age is neurotropin. The aim of this study was to investigate the effect of aerobic exercise with nitric oxide (NO) inhibition on neurotrypsin levels of soleus and extensor digitorum longus (EDL) musles in elderly rats.

old Wistar male rats (n=36, 20 months old) were randomly divided into six groups: 1) control, 2) control-25 (with NO inhibition using L-NAME at a daily dose of 25mg/Kg), 3) control 100, 4) exercise-25, 5) exercise-100, and 6) exercise. The training groups were exercised progressively on a treadmill for eight weeks, five days a week for 60 minutes at a speed of 28 m/min. The soleus and EDL musles were removed 48 hours after the last session of exercise training,.

In both muscles, a significant decrease in neurotropin was observed in the control-25 and control-100 compared to the control group, in the exercise group compared to the control group, in the exercise-25 compared to the control-25, and in the exercise-100 compared to the control-100.

In summary, the aerobic exercise reduces neurotropin levels, even with inhibition of nNOS. Therefore, aerobic exercise with a decrease in neurotropin and possibly a compensatory effect on increasing NO production in old age can play a role in maintain NMJ and delaying sarcopenia due to destabilization of the NMJ.