title: Protein metabolism in slow- and fast-twitch skeletal muscle during turpentine-induced inflammation.
abstract: The aim of our study was to evaluate the differences in protein and amino acid metabolism after subcutaneous turpentine administration in the soleus muscle (SOL), predominantly composed of red fibres, and the extensor digitorum longus muscle (EDL) composed of white fibres. Young rats (40-60 g) were injected subcutaneously with 0.2 ml of turpentine oil/100 g body weight (inflammation) or with the same volume of saline solution (control). Twenty-four hours later SOL and EDL were dissected and incubated in modified Krebs-Heinseleit buffer to estimate total and myofibrillar proteolysis, chymotrypsin-like activity of proteasome (CHTLA), leucine oxidation, protein synthesis and amino acid release into the medium. The data obtained demonstrate that in intact rats, all parameters measured except protein synthesis are significantly higher in SOL than in EDL. In turpentine treated animals, CHTLA increased and protein synthesis decreased significantly more in EDL. Release of leucine was inhibited significantly more in SOL. We conclude that turpentine-induced inflammation affects more CHTLA, protein synthesis and leucine release in EDL compared to SOL.
authors.affiliation: Department of Pharmacology and Toxicology, Faculty of Pharmacy, Charles University, Hradec Kralove, Czech Republic. muthnyt@faf.cuni.cz
authors.forename: Tomas
authors.initials: T
authors.lastname: Muthny
authors.forename: Miroslav
authors.initials: M
authors.lastname: Kovarik
authors.forename: Ludek
authors.initials: L
authors.lastname: Sispera
authors.forename: Ivan
authors.initials: I
authors.lastname: Tilser
authors.forename: Milan
authors.initials: M
authors.lastname: Holecek
mesh_terms: D000818:Animals; D007249:Inflammation / Q000139:chemically induced*; D007930:Leucine / Q000378:metabolism*; D008297:Male; D018656:Muscle Fibers, Fast-Twitch / Q000187:drug effects*; D018657:Muscle Fibers, Slow-Twitch / Q000187:drug effects*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D014425:Turpentine / Q000494:pharmacology*
chemical_list: D046988:Proteasome Endopeptidase Complex; D007930:Leucine; D014425:Turpentine