Renal Blood Flow and Function in the Rabbit After Surgical Trauma

Abstract

The renal artery was occluded in rabbits for varying lengths of time with the aid of a balloon catheter. Before and after the period of ischaemia, renal blood flow was measured by a dye-dilution technique and the glomerular and tubular functions were evaluated by measuring the extractions of labelled EDTA and Hippuran. Prolongation of the period of continuous ischaemia from 15 to 60 minutes resulted in a progressive increase in the postocclusive hyperaemia, but in a reduction of the renal function. Compared with 30 minutes of continuous occlusion, 30 minutes of intermittent occlusion caused only slight hyperaemia, but the same degree of reduction in renal function. One day after 30 minutes or 60 minutes of ischaemia, renal blood flow was within the range of the normal flow. After 30 minutes of occlusion, renal function was re-established 7 days later, whereas after 60 minutes of ischaemia, function was still severely impaired 7 days later. Fourteen days after 60 minutes of occlusion, renal function was 50% or less of the normal. Juxtamedullary shunting has not been demonstrated in the present investigation. Metabolic changes and cellular damage remain as possible explanations of the postocclusive changes in renal blood flow and function.