Motor nerve regulates muscle extracellular matrix proteoglycan expression.
Denervation of rat leg muscles caused a 2-3-fold increase in 35S-sulfate and 3H-glucosamine incorporation into proteoglycans of the muscle extracellular matrix. The size of the proteoglycans and the glycosaminoglycan chain length and degree of sulfation were unchanged. Because the rate of degradation of proteoglycans was also unchanged by denervation, we infer that denervation increases proteoglycan synthesis. Muscle reinnervation restored the original rate of synthesis of proteoglycans. Paralysis of innervated muscle caused increased incorporation of sulfate comparable to that seen in denervation. Thus motor nerve activity appears to regulate the level of proteoglycans in the muscle extracellular matrix.
Fadic
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R
Department of Cell and Molecular Biology, Faculty of Biological Sciences, Catholic University of Chile, Santiago.
Brandan
E
E
Inestrosa
N C
NC
D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D002852:Chromatography, Ion Exchange; D005109:Extracellular Matrix / Q000378:metabolism*; D005944:Glucosamine / Q000378:metabolism; D006025:Glycosaminoglycans / Q000096:biosynthesis* / Q000302:isolation & purification; D007700:Kinetics; D008297:Male; D008715:Methionine / Q000378:metabolism; D009046:Motor Neurons / Q000502:physiology*; D009121:Muscle Denervation; D009132:Muscles / Q000187:drug effects / Q000378:metabolism*; D011509:Proteoglycans / Q000096:biosynthesis* / Q000302:isolation & purification; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values; D013779:Tetrodotoxin / Q000494:pharmacology
D006025:Glycosaminoglycans; D011509:Proteoglycans; D013779:Tetrodotoxin; D008715:Methionine; D000110:Acetylcholinesterase; D005944:Glucosamine