SC-9420 (or Aldactone), an antimineralocorticoid spirolactone significantly protects against the mortality and some of the cardiovascular-renal changes normally produced by the presence of an ischemic (or “endocrine”) kidney in rats. Since Aldactone acts similarly on the manifestations of desoxycorticosteronc ovcrdosage, this, together with previous findings, indicates a close relationship between the toxic effects of mineralocorticoids and those of renal secretory products. Steroid spirolactones may prove to be useful against cardiovascular damage in clinical cases of renal hypertension.