we propose a distribution of na ( + ) in smooth muscle cells in two intracellular compartments : ( 1 ) na ( + ) freely dissolved in the sarcoplasm , exchanging with the kinetics of compartment b and ( 2 ) a second cellular compartment which could be contained in the sarcoplasmic reticulum exchanging with the kinetics of compartment c.6 .
C0007634
cellular
C0036226
sarcoplasmic reticulum