Modification in the Locomotor Activity of the Rat Soleus Muscle in Response to Hindlimb Unloading: Preliminary Results

Abstract

In rats, previous studies have shown that hindlimb unloading (HU) modifies muscle characteristics, especially in antigravitational muscles such as the soleus (SOL). However, little is known about the neural effects of unloading. Some authors have found that the EMG activity in the rat SOL during HU is significantly reduced, and that the patterns of activity are changed (Blewett & Elder, 1993). Locomotion has not yet been studied after HU, but some clinical studies are of particular interest. It has been demonstrated that i) many locomotor disorders are due to a muscular deficit; ii) an adaptation of the locomotor pattern can occur in order to maintain the muscular system performance, in spite of muscle changes. This data supports the idea that the locomotor pattern may be modified, in response to HU and to its associated muscular transformation.