Effects of cimaterol on rabbit growth and myofibrillar protein degradation and on calcium-dependent proteinase and calpastatin activities in skeletal muscle.

摘要: The objectives of this study were to examine effects a beta-adrenergic agonist (cimaterol) on growth and muscle development in rabbits cimaterol's myofibrillar protein degradation (MPD) activities several proteolytic enzymes including the calcium-dependent proteinases (CDP). Twelve New Zealand White assigned either control diets or containing cimaterol for 35 d, after which they killed performance tissue weight gains determined. Urine was collected from d 21 through 28 each rabbit assessment N tau-methylhistidine (NMH) excretion. Cimaterol increased rates gain, efficiency gain skeletal weights. Enhancement associated with an increase total DNA reduction NMH. did not affect cathepsin B, D neutral serine proteinase, but it reduced millimolar micromolar forms CDP by 58 57%, respectively, activity inhibitor (calpastatin) 52%. Cimaterol-dependent accretion likely mediated, at least part, MPD. change MPD activities. hypertrophy therefore may involve changes proteolysis proteins. significance calpastatin is known.