Plasma levels and renal removal of gastrin after acute hepatic ischemia in dogs.

Plasma levels and renal uptake of gastrin were determined in ten dogs submitted to complete liver devascularization in order to induce an acute liver failure. Renal function was evaluated by renal plasma flow (RPF) and glomerular filtration rate (GFR) determinations. Liver devascularization was obtained by end-to-side porto-caval shunt (PCS) followed by temporary clamping of the hepatic artery. PCS alone did not affect renal function and renal ability to remove gastrin; after hepatic ischemia, both RPF, GFR and renal extraction of gastrin showed an abrupt decrease. At the end of the period of hepatic ischemia 5 dogs were submitted to glucose infusion, in consideration that: i) glucagon is able both to affect gastrin release and renal hemodynamics, and ii) hypoglycemia that develops after liver failure releases elevated amounts of glucagon. The renal handling of gastrin was not related to glucagon plasma levels, though the higher gastrin levels occurred at the lower glucagon concentrations. These data suggest that in acute liver failure there is a striking decrease of the renal clearance of gastrin associated with the impairment of kidney function. Furthermore, in this pathological condition plasma gastrin levels are affected by blood glucose concentrations through its effect on plasma glucagon levels.