Effects of 9 weeks hindlimb suspension on neuromuscular activity patterns in rat

It is well known that gravitational unloading induces muscle atrophy associated with a shift of fiber type in slow-twitch muscle. Ishihara et al. (1996 & 1997) reported that 2 weeks of spaceflight caused a decrease in succinate dehydrogenase activities of ventral horn and dorsal root ganglion neurons in rats. Significant effects on motor performance are also induced in both human (Kozlovskaya et al., 1981) and rats (Canu and Falempin, 1997), but these changes are reversible. However, it is not known how neuromuscular function respond to long-term gravitational unloading. Therefore, the current study was carried out to investigate the effects of 9 weeks of hindlimb suspension on the neuromuscular function and mass in hindlimb muscles in rats.