L-arginine enhances muscle regeneration after experimental envenomation by B. jararacussu: A future for nitric oxide-based therapy?

Abstract

We investigated whether muscle fiber regeneration would be rescued by exogenous administration of l-arginine, the precursor of endogenous synthesis of nitric oxide. The right tibialis anterioris muscle of adult mice ( n = 20 ) was injected with 80 μg of venom. One group of mice ( n = 10 ) received drinking water containing l-arginine (3.75 mg/ml) and another group ( n = 10 ) did not receive any pharmacological treatment. Two months later, muscle regeneration was evaluated by counting the total number of muscle fibers. We found that in l-arginine-treated mice, muscle regeneration was significantly higher ( p < 0.05 ) than in saline-treated ( 2.230 ± 478 muscle fibers versus 1.005 ± 134 , respectively) although the level of muscle fiber population of uninjured tibialis anterioris muscle ( 3.121 ± 102 ) was not attained. These results show that muscle regeneration was significantly facilitated by l-arginine and suggest that pharmacological activators of the NO pathway may be potentially useful for improving muscle regeneration in human envenomation by B. jararacussu.