title: Lysosomes in skeletal muscle tissue. Zonal centrifugation evidence for multiple cellular sources.
abstract: Postnuclear supernates from homogenates of skeletal muscle from rats subjected to starvation, injections of Triton WR-1339, dextran-500, and dextran + corticosterone were fractionated by means of rate and isopycnic zonal centrifugation in sucrose-0.02 M KCl gradients. Zonal fractions were analyzed for protein, RNA, cytochrome oxidase, and up to six acid hydrolases. The results indicate the presence of two groups of lysosome-like particles. One group contributes approximately 95% of the cathepsin D and acid phosphatase activity and 75% of the acid ribonuclease, beta-glucuronidase, and arylsulfatase activity in muscle. It is characterized by a modal equilibrium density of 1.18 that is decreased by starvation, but is not shifted by dextran-500 or Triton WR-1339. The second group has a higher proportion of acid ribonuclease, beta-glucuronidase, and arylsulftase; the equilibrium density can be shifted by dextran-500 and Triton WR-1339. It is suggested that this group of lysosomes is derived from macrophages and other connective tissue cells, whereas the former group represents lysosome-like particles from muscle cells.
mesh_terms: D000135:Acid Phosphatase / Q000032:analysis; D000818:Animals; D002403:Cathepsins / Q000032:analysis; D002458:Cell Fractionation; D002501:Centrifugation, Zonal; D003345:Corticosterone / Q000494:pharmacology; D003902:Detergents / Q000494:pharmacology; D003911:Dextrans / Q000494:pharmacology; D003956:Dialysis; D003576:Electron Transport Complex IV / Q000032:analysis; D005966:Glucuronidase / Q000032:analysis; D008247:Lysosomes / Q000032:analysis / Q000201:enzymology*; D008722:Methods; D009113:Muramidase / Q000032:analysis; D009124:Muscle Proteins / Q000032:analysis; D009132:Muscles / Q000166:cytology*; D010587:Phagocytosis; D011506:Proteins / Q000032:analysis; D012313:RNA / Q000032:analysis; D051381:Rats; D012260:Ribonucleases / Q000032:analysis; D013217:Starvation; D013997:Time Factors; D014020:Tissue Extracts
chemical_list: D003902:Detergents; D003911:Dextrans; D009124:Muscle Proteins; D011506:Proteins; D014020:Tissue Extracts; D012313:RNA; D003576:Electron Transport Complex IV; D012260:Ribonucleases; D000135:Acid Phosphatase; D009113:Muramidase; D005966:Glucuronidase; D002403:Cathepsins; D003345:Corticosterone