Capillary fiber ratio and electrolyte content of compensatory hypertrophied rat soleus

Abstract Capillary-to-fiber ratio and the content (μmoles/g muscle) of Na, K, Mg, Ca and Zn was measured in compensatory hypertrophied (CH) soleus muscles of adult Sprague-Dawley rats. The soleus hypertrophy was induced by unilateral tenotomy of the gastrocnemius and the plantaris muscles. Seven days after synergistic tenotomy the compensatory hypertrophied Soleus muscles showed no difference in the capillary-fiber ratio, Sr-extractable calcium ([Ca] Ext. ) or the total content of Na, K, Mg and Zn. However, compared to the contralateral control side, the CH muscles showed an increase in the wet muscle weight (31.6%, P P Res. ) and 43.2% ( P Total ) content. It is concluded that during compensatory hypertrophy of skeletal muscles, the residual Ca reserves are significantly depleted, which may lead to a lower isometric tension generation in the muscle.