Haemodynamic characterization of the isolated (denervated) parabiotically perfused rat jejunum

The isolated (denervated) parabiotically perfused rat jejunum was characterized for base-line haemodynamics, autoregulation of blood flow and oxygen consumption and long-term (3 h) stability with respect to both haemodynamics and the absence of tissue injury. In short-term experiments, the parabiotically perfused preparation autoregulated oxygen consumption but not blood flow over a wide range of perfusion pressures (25-85 mmHg). When the intestinal segment was subjected to near total ischaemia for I h, followed by I h of reperfusion, mucosal injury was induced which could be prevented by i.v. administration of superoxide dismutase after ischaemia just prior to reperfusion, or allopurinol prior to ischaemia. These findings support the concept of post-ischaemic reperfusion injury in the denervated preparation without hepatic ischaemia. This preparation could thus serve as an improved model for the study of the pathophysiology of post-ischaemic reperfusion injury in the rat intestine.