to further define the cellular basis for these changes , the present study was designed to characterize age-related changes in ca2+ transport in sarcoplasmic reticulum ( sr ) vesicles isolated from six groups of sheep : group ( sp ) i ( 100-105 days gestation ) , gp ii ( 128-132 days gestation ) , gp iii ( postnatal , 0-3 days ) , gp iv ( 4 wk ) , gp v ( 8 wk ) , and gp vi ( maternal sheep ) .
C0007634
cellular
C0036226
sarcoplasmic reticulum