EFFECTS OF CHRONIC EXCESS SALT INGESTION : ROLE OF GENETIC FACTORS IN BOTH DOCA-SALT AND RENAL HYPERTENSION

By selective inbreeding, two strains of rats were developed previously that differed markedly in their susceptibility to the development of experimental hypertension from excess salt ingestion (1, 2). The present report indicates that with animals derived from the same strains, similar differences in response were obtained in rats subjected to either combined desoxycorticosterone-NaCl (DOCA-salt) treatment or unilateral renal artery compression without extra dietary salt. Thus differences in genetic substrate appear to influence the development of experimental hypertension produced by these three techniques and possibly this may hold true for all "varieties" of experimental hypertension. If true, it might allow the development of a unifying hypothesis that could be relevant not only to experimental hypertension but perhaps to human hypertension as well. The DOCA-salt regimen was more toxic to the animals than unilateral renal artery compression. Tentatively, this was ascribed to either, or both, the younger age or the higher NaCl intake of the animals in the former.