THE RENAL PATHOLOGY OF NUTRITIONAL HYPERTENSION IN RATS.

Rats subsisting on a diet partially deficient in the heat-stable fractions of the vitamin B complex are known to experience a rise in blood pressure. The present study shows that after prolonged administration of this dietary, abnormal structural changes occur in the kidneys. The surface of this organ becomes finely granular. The afferent arterioles show degenerative changes, consisting of irregular subendothelial hyaline deposits which encroach on the lumen. The interlobular arteries undergo the same change, plus degeneration of the media; the lumen of these vessels is likewise compromised. Resultant, small, streak-like areas of ischemic atrophy occur in both cortex and medulla, with necrosis of the epithelial lining of the uriniferous tubules. The glomeruli are reduced in size, the number of their component loops decreased, their pattern simplified, and the capillary basement membrane thickened. In addition to these changes, kidneys from animals on a more profoundly deficient diet display numerous areas of hemorrhagic infiltration in the cortical and subcapsular regions. The possible identity of these lesions with those seen in essential hypertension in man is discussed.