Chloride as a Determinant of Salt-Sensitivity

Abstract

In some patients with essential hypertension, blood pressure decreases with restriction of dietary salt (NaCI, sodium chloride) and increases with its subsequent supplementation — responses now said to characterize “salt-sensitive” hypertension (Fujita et al. 1980). Although Ambard and Beaujard suggested in 1904 that increased retention of chloride might be involved in the pathogenesis of hypertension (Ambard and Beaujard 1904), a half century later Dahl asserted that “the sodium ion alone is important” in the hypertensinogenic capacity of dietary NaCI (Dahl and Love 1954). The now prevalent view is that the capacity of sodium chloride to increase blood pressure depends only on its sodium component and that, hence, all commonly ingested sodium salts have this capacity (Dahl 1960; Wallis 1982; Jacobson et al. 1983). However, the results from studies performed over 50 years ago, as well as from more recent studies, provide support for an alternative hypothesis: For NaCI to increase blood pressure, both its sodium and chloride components are necessary; hence, restriction of either sodium or chloride may be sufficient to attenuate a NaCl-induced increase in blood pressure.