Heymann nephritis-DOCA-NaCl hypertension in the rat. Role of nephritis, DOCA, NaCl, and vascular lesions in the development of hypertension.

In order to explore the impact of nephritis on the development of hypertension, rats with Heymann nephritis were given 0.9% NaCl to drink, in combination with or without DOCA injections, for up to 6 months. Combined nephritis-DOCA-NaCl resulted in severe hypertension and shortened life span, whereas nephritis-NaCl combination failed to induce hypertension or shorten life span. All immunized rats developed membranous glomerulonephritis but creatinine clearance did not decrease. DOCA-NaCl-treated nephritic rats had a heavier proteinuria and more marked renal lesions than NaCl-treated nephritis rats. Proliferative-sclerotic glomerular lesions were seen in the nephritis-DOCA-NaCl group only, correlating to the severity of hypertension. Other renal and extrarenal vascular lesions, increasing with time, also appeared related to the severity of hypertension. This suggests a secondary relationship of vascular damage to hypertension in this model. Appearance of proteinuria preceded the establishment of hypertension, suggesting that nephritis sensitized to the development of hypertension during DOCA-NaCl treatment. Sodium excess alone, however, did not induce hypertension in Heymann nephritic rats. The present Heymann nephritis-DOCA-NaCl hypertension model appears a useful model for the study of hypertension complicating glomerulonephritis.