[Effect of thyroxine on the phenotype of intact and denervated skeletal muscles in the guinea pig]. / Vliianie tiroksina na fenotip intaktnykh i denervirovannykh skeletnykh myshts morskoi svinki.

ABSTRACT

Denervation of the guinea-pig fast (m. plantaris) and slow (m. soleus) muscles, administration of alpha-thyroxine (T4) to animals followed by denervation and T4 injection entail changes in the relative content of different types of muscle fibers. The slow muscle shows fast muscle fibers after T4 injection, denervation and T4 injection. Moreover, myosin isolated from the m. soleus shows the precipitation band with antibodies to fast muscle myosin. These data attest to partial reprogramming of myosin synthesis by the m. soleus, pointing to the role played by thyroxine in myosin synthesis regulation.