Sodium withdrawal contractures in developing and regenerating rat extensor digitorum longus muscles.
During postnatal development of extensor digitorum longus (EDL) muscle, sodium withdrawal contractures were observed during the first 6 days after birth, and not after this time. In regenerating EDL muscles, zero-Na contractures were demonstrated: (1) 7 days after bupivacaine injection, but not 14 or 90 days after this injection; (2) 7, 14, and 90 days after autotransplantation; and (3) 7, 14, and 90 days after the intervention in sliced muscles. The present findings emphasize the role of the denervation in the development of zero-Na contractures in the regenerating muscles and suggest that a calcium-sodium exchange across the sarcolemma may appear in these muscles.
Laboratory of Cellular and Molecular Physiopathology and Pharmacology, CJF Inserm 96-01, CHR G.R. Laennec, Nantes, France.
J P
JP
Louboutin
J
J
Noireaud
D000779:Anesthetics, Local / Q000494:pharmacology; D000818:Animals; D002045:Bupivacaine / Q000494:pharmacology; D002118:Calcium / Q000502:physiology; D003286:Contracture / Q000139:chemically induced / Q000503:physiopathology*; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects / Q000502:physiology; D024510:Muscle Development; D018482:Muscle, Skeletal / Q000254:growth & development / Q000502:physiology* / Q000637:transplantation*; D051381:Rats; D017208:Rats, Wistar; D012038:Regeneration / Q000502:physiology*; D012965:Sodium Chloride / Q000494:pharmacology*; D019789:Tetraethylammonium / Q000494:pharmacology
D000779:Anesthetics, Local; D012965:Sodium Chloride; D019789:Tetraethylammonium; D002118:Calcium; D002045:Bupivacaine