Investigating the myopathic effects of 6-mercaptopurine on developing skeletal muscle cells in vitro.
6-Mercaptopurine (6-MP) is an adenine antagonist which has been shown to cause skeletal muscle atrophy in neonatal rats. To investigate the effects of 6-MP on developing muscles, pure populations of myoblasts and myotubes in vitro were treated with 6-MP (5-50 micrograms/ml). The viability and protein content of myotubes, but not myoblasts, was decreased by 6-MP. Microscopic examination of the 6-MP-treated (50 micrograms/ml) myotubes demonstrated that severe degenerative changes had occurred, including extensive necrosis, inhibition of myotube formation, and the appearance of intracellular vacuoles. However, 6-MP treatment decreased the incorporation of radiolabeled leucine and thymidine by myoblasts, but not myotubes. These findings indicate that 6-MP exerted a selective toxicity on myotubes but not myoblasts.
D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D002642:Chick Embryo; D004247:DNA / Q000096:biosynthesis; D066298:In Vitro Techniques; D007930:Leucine / Q000378:metabolism; D015122:Mercaptopurine / Q000633:toxicity*; D008870:Microtubules / Q000378:metabolism; D009124:Muscle Proteins / Q000378:metabolism; D009132:Muscles / Q000187:drug effects / Q000378:metabolism; D009135:Muscular Diseases / Q000139:chemically induced*; D013936:Thymidine / Q000378:metabolism
D009124:Muscle Proteins; D004247:DNA; D015122:Mercaptopurine; D007930:Leucine; D013936:Thymidine