Transverse tubular system in glycerol-treated skeletal muscle.

Horseradish peroxidase used as an extracellular marker fills 98.5 percent of the central triadic elements (tubules) in normal muscle and 97.2 percent in muscle soaked in Ringer solution to which 400-millimolar glycerol is added. A glycerol-soaked muscle rapidly returned to normal Ringer solution has a disrupted transverse tubular system and has only 3.2 percent of triads filled with peroxidase.