Plasma fatty acids response to central volume expansion in salt-sensitive hypertension

The purpose of the present study was to invèstigate the possible regulation of plasma latty acids by an acuts isotonic-isooncotic central volume expansion. We méasured the levels of nonesterified fatty acids (NEFA) in plasrna from 12 essential hypertensive patlents subjected to water immersion (Wl). Central hypervolemia by Wl over 2 hours caused the levels of most NEFA to increase, concomitantly with a marked natriuretic and kaliuretic response. With respect to baseline values, serum insulin levels did not change during Wl, while there was a profound suppression of plasma renin activity (PRA) and plasma aldosterone, In addition, when individual NEFA percent increase was expressed as a function of salt-sensitivity index calculated as the change in mean arterial pressure IMAPI divided by the change in urinary sodium excretion rate), a grèater percent increase in stearic acid (r=.72, P<.009), palmitic acid{r=.83,P<.001),and palmitoleic acld (r=.58.P<.048) was found during Wl in those hypertensivè subjects showing higher saltsensitivity index. Thus, by demonstrating that an acute isolonic-isooncotlc volume expansion may induce a signiflcant increase of most NEFA plasma lèvels, we suggest that volume èxpansion per se could be included among ths well-recognized risk factors for cardiovascular morbid evènts.