EFFECT OF EXPERIMENTAL NEUROGENIC HYPERTENSION ON RENAL BLOOD FLOW AND GLOMERULAR FILTRATION RATES IN INTACT DENERVATED KIDNEYS OF UNANESTHETIZED RABBITS WITH ADRENAL GLANDS DEMEDULLATED

Abstract

The relative autonomy of the renal circulation persists in unanesthetized rabbits, particularly with reference to increases in blood pressure, even in animals with kidneys denervated and adrenal glands demedullated. Acute neurogenic blood pressure elevations were experimentally induced and clearance techniques employed to measure the effect of pressure increases on renal plasma flow and glomerular filtration rates in 10 [male] rabbits. A mean pressure rise of 43% for all animals studied was accompanied by an increase in renal plasma flow of 5%, and in glomerular filtration rate of 8%. Three of the animals showed decreased renal plasma flow with the increase in blood pressure, and a fall in glomerular filtration rate was noted in one. A rise in resistance afferent to the glomeruli accompanies blood pressure elevation. The basic mechanism accountable for this pressure-flow accommodation remains obscure.