Objective: To study changes in electrophysiological characteristics of muscle spindles induced by simulated weightlessness in isolated rats soleus.
Method: Weightlessness was simulated by tail-suspension in female rats. Using electro-physiological technique, the spontaneous discharge of muscle spindle and its response to ramp-and-hold stretch were observed in isolated soleus of 7 d, 14 d tail-suspended and control rats.
Result: Soleus muscle spindles of rat manifest a sharp decrease in spontaneous discharge frequency and the response to ramp-and-hold stretch after 7 d tail-suspension. More significant changes were observed in rats after 14 d tail-suspension.
Conclusion: Simulated weightlessness could induce time-related changes in electrophysiological characteristics of soleus muscle spindles in rat.
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