these results lend support to the hypothesis that the sarcoplasmic reticulum of phasic muscle , in addition to its specialized role in excitation-contraction coupling , represents a multifunctional membrane system , and that , similar to the smooth endoplasmic reticulum of other cells , it includes some membrane-bound lysosomal enzymes and nadh oxidase .
C0036226
sarcoplasmic reticulum
C0007634
cells