TY - JOUR
T1 - Myosin heavy chain mRNA and protein expression in single fibers of the rat soleus following reinnervation
AU - Bodine, Sue C.
AU - Pierotti, David J.
N1 - Funding Information:
This work was supported by a Merit Grant from the VA Research Services.
PY - 1996/8/30
Y1 - 1996/8/30
N2 - Myosin heavy chain (MHC) expression is regulated by many factors including neural input. To gain a better understanding of myosin transformation following reinnervation we examined both MHC protein and mRNA in single fibers of the soleus. A midthigh sciatic nerve lesion resulted in reinnervation of the soleus by motoneurons from both the original and foreign motor pools. MHC expression was examined in individual fibers 8 and 16 weeks post injury using in situ histochemistry and immunohistochemistry. Following a sciatic nerve lesion, the reinnervated soleus underwent a transformation from slow toward fast based on physiologic and biochemical measurements. At 8 weeks, fast MHC mRNA isoforms (IIa and IIx) were upregulated and slow mRNA was downregulated, however, the predominant protein isoform was MHC I. At both 8 and 16 weeks, many fibers expressed multiple mRNA isoforms. At 16 weeks there was limited co-expression of slow and fast MHC mRNAs, but continued co-expression of fast MHC mRNAs. Sixteen weeks following reinnervation the predominant fast mRNA and protein in the soleus was IIx MHC.
AB - Myosin heavy chain (MHC) expression is regulated by many factors including neural input. To gain a better understanding of myosin transformation following reinnervation we examined both MHC protein and mRNA in single fibers of the soleus. A midthigh sciatic nerve lesion resulted in reinnervation of the soleus by motoneurons from both the original and foreign motor pools. MHC expression was examined in individual fibers 8 and 16 weeks post injury using in situ histochemistry and immunohistochemistry. Following a sciatic nerve lesion, the reinnervated soleus underwent a transformation from slow toward fast based on physiologic and biochemical measurements. At 8 weeks, fast MHC mRNA isoforms (IIa and IIx) were upregulated and slow mRNA was downregulated, however, the predominant protein isoform was MHC I. At both 8 and 16 weeks, many fibers expressed multiple mRNA isoforms. At 16 weeks there was limited co-expression of slow and fast MHC mRNAs, but continued co-expression of fast MHC mRNAs. Sixteen weeks following reinnervation the predominant fast mRNA and protein in the soleus was IIx MHC.
KW - Denervation
KW - Immunohistochemistry
KW - In situ histochemistry
KW - Myosin heavy chain gene regulation
KW - Sciatic nerve injury
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U2 - 10.1016/S0304-3940(96)12926-8
DO - 10.1016/S0304-3940(96)12926-8
M3 - Article
C2 - 8880742
AN - SCOPUS:0030606801
VL - 215
SP - 13
EP - 16
JO - Neuroscience Letters
JF - Neuroscience Letters
SN - 0304-3940
IS - 1
ER -