Pressure-flow studies in the isolated artificial heart-lung perfused mammalian kidney

Abstract

This study attempts to define some of the physiologic characteristics of the isolated whole blood artificial heart-lung perfused rabbit kidney and describes a modification of an original method previously described. The effects of anesthesia of the kidney donor animal with intraperitoneal ethyl alcohol, intravenous sodium pentobarbital and cervical spinal cord transection (performed on unanesthetized animals) have been compared in terms of renal function and the relationship of renal blood flow to changing perfusion pressures. When spinal cord transection was used, relatively normal levels of renal function were obtained in better than 90% of the experiments. Average values for 12 experiments are: observed renal plasma flow = 1.70; creatinine and p-aminohippuric acid (PAH) clearance = .28 and 1.3 ml/min/gm kidney weight; PAH extraction = 75%; and U:P ratios for creatinine and glucose = 26:1 and 0.1:1. Autoregulation of renal blood flow was demonstrated in a completely denervated kidney perfused with whole blood but was abolished when alcohol anesthesia was used in the kidney donor rabbit. There appeared to be no correlation between the presence or absence of this phenomenon and the level of clearance function achieved by the kidney.