TARDY EFFECT OF NEUROGENIC MUSCULAR-ATROPHY BY MAGNETIC STIMULATION

The influence of pulsed magnetic stimulation on denervated muscles was investigated in this study. Of 24 rats divided into three groups for experiment, 8 rats served as control; 16 rats with bilaterally severed sciatic nerves were divided into two groups for different modes of st imulation. Magnetic stimulation with a high power output that induced an intensive contraction of muscle was applied at one side-denervated gastrocnemius muscle for 1 mo in a group of rats; electric stimulation with high intensity at 6 Hz frequency and 1-ms pulse duration served as a contrast in the other group. Muscular weight, volume, fiber diame ter and percentage of fiber types were measured after the experiment. A significant retardation of weight loss in denervated muscles via mag netic stimulation (P < 0.05) was confirmed by observed results. Type I I fiber atrophy was retarded in denervated muscles by magnetic stimula tion as well as in denervated muscles via electric stimulation. Magnet ic stimulation, used as a method that induces muscular activity, was v erified in this study as being capable of retarding denervated muscula r atrophy. Its benefits of painless stimulation as well as deeply acti vated muscular contraction could be expected to function as a new mode l for rehabilitation of paralyzed muscles.