A possible purinergic mechanism for reactive ischemia in isolated, cross-circulated rat kidney.

The isolated kidney of the recipient rat was perfused at a fixed flow rate with blood from a donor by a cross-circulation technique. The renal vasculature responded to the release of arterial occlusion with vasoconstriction, the magnitude of which was increased with increase in the duration of occlusion. ATP, ADP, AMP, adenosine, noradrenaline and 5-HT injected into the renal artery induced a prominent vasoconstriction; IMP and inosine had only a weak vasoconstrictor effect even in large doses. Theophylline reduced the vasoconstriction in response to arterial occlusion and to ATP and adenosine but did not affect that produced by noradrenaline or 5-HT. This suggests that adenine compounds, particularly adenosine, may play a role in the genesis of reactive vasoconstriction after arterial occlusion in the isolated rat kidney.