Denervation Diuresis and Renin Secretion in the Anaesthetized Dog

Simultaneous determinations of renal sodium excretion and renin secretion have been performed on 10 anaesthetized dogs, 1–2 weeks after unilateral splanchnicotomy (“renal denervation”). Under basal conditions, urine flow and sodium excretion were increased, renal venous renin activity (RVRA) and secretion decreased on the denervated side. During isotonic volume expansion a quantitative increase in denervation diuresis and natriuresis occurred while RVRA in denervated kidneys decreased further and the secretion rate became negative. Regardless of the absolute differences in water and sodium excretion between intact and denervated kidneys, RVRA and the output of the latter amounted to about 60 per cent of the intact kidney values. Both sodium reabsorption and renin production seem to be neurally regulated; their interrelationship is discussed.