Tabary et al. (1981) accelerated serial sarcomere loss by applying electrical stimulation, resulting in a 25% decrease in sarcomere number (SN) in the guinea pig soleus muscle within 12 hours. A duplication of these results was attempted in our laboratory. Rabbit lower hind limb muscles were stimulated for 10 hours continuously. As a result, muscles lost approximately 25% of sarcomeres in series.
During laser diffraction analysis, it was observed that the first order diffraction band was wider in experimental compared to control muscles, implying some form of non-uniformity within the fascicle. Therefore, sarcomere length non-uniformity and structural disorganization was analyzed using light microscopy. Electrical stimulation indeed caused an increase in SL non-uniformity.
In an attempt to examine the possibility of sarcomere loss in a more clinically relevant environment, muscle morphology and SN was analyzed in the genetically spastic mouse. The gastrocnemius muscle was shorter, but SN was generally unchanged.