Hemodynamics and Sodium Excretion of Denervated Kidney in Anesthetized and Unanesthetized Dog

Abstract

Functions of the normal and denervated kidneys were studied in anesthetized and trained unanesthetized dogs. The left kidney was denervated from 6-49 days prior to the actual expts. Renal plasma flow (RPF) glomerular filtration rate (GFR) and Na excretion were significantly greater in the denervated kidney of the anesthetized dog as compared to the unanesthetized animal in which they were essentially equal. TmPHA and Tm glucose were unaffected by denervation. Admn. of a non-electrolyte diuretic (mannitol in anesthetized and glucose in unanesthetized dogs) did not result in a significant difference in urine Na concn. of the 2 kidneys. In 1 expt. after a pair of clearance periods in the unanesthetized state, pento-barbital anesthesia produced a considerable reduction of RFF , GFR, Na and water excretion, and urine Na concn. in the innervated kidney without affecting the function of the denervated kidney. Emotional stress brought about a similar, but less marked, depression of RPF, GFR and Na excretion in the normal kidney. Na excretion appears to be dependent on GFR and there is no evidence in these expts. that chronic denervation per se affects tubular reabsorption of Na. The difference in function of the normal and denervated kidneys found in many of the expts. on anesthetized dogs, and the decrease in RPF, GFR and Na excretion observed in the control kidney of unanesthetized dogs subjected to stress is believed to be due to reflex vasoconstriction of the normal innervated kidney.