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.