1. Addition of nifedipine to a high salt diet prevented the development of malignant hypertension in the Dahl salt-sensitive strain (Brookhaven) of rats (DS rats).
2. In DS rats with a pre-existent malignant hypertension nifedipine normalized blood pressure, which then correlated with a lower incidence and degree of vasculopathy.
3. Nifedipine appeared to counteract the effect of a supposed humoral pressor agent in DS rats.