Blood flow in the portal vein and the left gastric artery was measured electromagnetically and gastric mucosal perfusion was determined by pertechnetate clearance in anaesthetized dogs. Bleeding the animals to arterial pressures of 100 and 60 mmHg respectively reduced portal venous flow and markedly increased the mesenteric inflow resistance. Left gastric arterial and gastric mucosal blood flow were decreased without significant vascular resistance change only in proportion to perfusion pressure reduction. Gastric acid output decreased but did not stop even at the lower level of haemorrhagic hypotension. It is concluded that ischaemia and acid, probably in the presence of regurgitated bile, may play an important role in the development of stress ulcers.
Animals Dogs