in contrast to saline-infused controls and following epinephrine infusion , where these tracers always remained extracellular , norepinephrine- and isoproterenol-infused animals exhibited alteration of sarcoplasmic membrane permeability to macromolecules in the early stage of evolution preceding fine structural changes of cardiac muscle cells .
C0014563
epinephrine
C0028351
norepinephrine