Biochemical and morphological characteristics of calcium uptake by denervated skeletal muscle

Calcium uptake by sarcoplasmic reticulum vesicles from batrachotoxin- or surgically denervated muscle was measured by both isotopic and energy dispersal X-ray procedures. In the presence of inorganic phosphate, vesicles obtained from both chemically and surgically denervated muscle accumulated less calcium than control vesicles. Intravesicular calcium appeared to be present either as a crystalline or granular precipitate. Our results support the concept that batrachotoxin, by blocking both axonal transport and impulse activity, results in a chemical denervation of the muscle.