Cytotoxic action of the lysosomotropic agent L-leucine methyl ester on mammalian skeletal muscle. The role of the sarcoplasmic reticulum in producing myofilament damage.
Incubation in vitro of mouse or rat diaphragms or mouse soleus muscle with the lysosomotropic agent leucine methyl ester (10 mM) produced a slowly-developing swelling of the sarcoplasmic reticulum (SR), showing that this organelle is able to take up amino acid methyl esters and conforming with previous suggestions that the SR may serve some of the functions of the lysosomal system in muscle cells. Cellular damage followed, sometimes associated with the shrinkage of the SR, but experiments with inhibitors of lysosomal cathepsins suggest that acid hydrolases were not implicated in this damage. It is suggested that the system producing myofilament damage is located on the SR and that it may be directly activated by membrane perturbation.
Shamsadeen
N
N
Department of Zoology, University of Liverpool, UK.
Duncan
C J
CJ
D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D003964:Diaphragm; D007930:Leucine / Q000031:analogs & derivatives* / Q000494:pharmacology; D008247:Lysosomes / Q000187:drug effects / Q000648:ultrastructure*; D051379:Mice; D008807:Mice, Inbred BALB C; D008854:Microscopy, Electron; D009132:Muscles / Q000166:cytology* / Q000187:drug effects / Q000648:ultrastructure; D051381:Rats; D011919:Rats, Inbred Strains; D012519:Sarcoplasmic Reticulum / Q000187:drug effects / Q000648:ultrastructure
C030365:leucine methyl ester; D007930:Leucine