title: Comparative effects of thermal and surgical trauma on rat muscle protein metabolism.
abstract: A modified intraperitoneal pool flooding technique, employing L-3H-tyrosine, was developed for measuring muscle protein synthetic rates following traumatic injury. Sufficient radiolabeled tyrosine was injected intraperitoneally to effect a six-fold increase in plasma tyrosine concentration (124-800 microM) resulting in constant, sustained specific radioactivities in plasma- and intracellular-free tyrosine pools. Localized vs systemic effects of thermal and surgical trauma on gastrocnemius muscle protein turnover were assessed 2 and 4 days postinjury. Thermal trauma increased total, myofibrillar, and sarcoplasmic muscle protein synthesis (44%) and protein degradation (300%). Conversely, surgical trauma decreased synthesis of total (24%), myofibrillar (14%), and sarcoplasmic (43%) muscle proteins without altering protein degradation. Short-term restriction of pair-fed controls did not affect either aspect of protein turnover.
authors.affiliation: Department of Physiological Sciences, School of Veterinary Medicine, University of California, Davis 95616.
authors.forename: V L
authors.initials: VL
authors.lastname: Mermel
authors.forename: B M
authors.initials: BM
authors.lastname: Wolfe
authors.forename: R J
authors.initials: RJ
authors.lastname: Hansen
authors.forename: A J
authors.initials: AJ
authors.lastname: Clifford
mesh_terms: D000818:Animals; D001835:Body Weight; D002056:Burns / Q000378:metabolism*; D004435:Eating; D005260:Female; D007044:Hysterectomy; D009124:Muscle Proteins / Q000378:metabolism*; D009132:Muscles / Q000293:injuries* / Q000378:metabolism; D009210:Myofibrils / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism; D010529:Peritoneal Cavity; D051381:Rats; D011919:Rats, Inbred Strains; D012519:Sarcoplasmic Reticulum / Q000378:metabolism; D014443:Tyrosine / Q000097:blood / Q000378:metabolism
chemical_list: D009124:Muscle Proteins; D014443:Tyrosine; D009584:Nitrogen