however , a majority of the specific phospholamban labeling within 30 nm of the cytoplasmic side of the sarcolemma was clustered and present over the sarcoplasmic reticulum in the subsarcolemmal region of the myocardial cells , suggesting that phospholamban is confined to the junctional regions between the sarcolemma and the sarcoplasmic reticulum , but absent from the nonjunctional portion of the sarcolemma .
C0010834
cytoplasmic
C0007634
cells