Involvement of uptake2 mechanism in inactivation of noradrenaline released by tyramine under anoxic conditions in perfused rat heart.

Effects of uptake2 inhibition by corticosterone on tyramine-induced noradrenaline (NA) overflow under control, glucose-deprivation, anoxia and anoxia with glucose-deprivation were examined in perfused rat heart. Uptake2 inhibition by corticosterone (100 microM) had no effect on the NA overflow under control and glucose-deprivation, but significantly augmented the NA overflow by about 40% and 25% under anoxia and anoxia with glucose-deprivation, respectively. These results indicate that the uptake mechanism is at least in part responsible for the inactivation of NA under anoxic conditions in the perfused rat heart.