Effects of sodium citrate on salt sensitivity and kidney injury in chronic renal failure

Abstract

Metabolic acidosis, which is observed in salt-sensitive hypertension, is also associated with kidney injury. Alkali therapy in chronic renal failure (CRF) may ameliorate the progression of kidney disease; however, few studies have examined the effects of alkali therapy on salt sensitivity and kidney injury in CRF. We randomly administered standard diet (SD), sodium chloride with 20% casein diet (NACL), or sodium citrate with 20% casein diet (NACT) to Sprague-Dawley rats after a CRF or a sham operation. Four weeks after 5/6 nephrectomy, serum bicarbonate levels were higher in the NACT-treated group. On the pressurenatriuresis curve, NACT-treated CRF rats were more salt-resistant than NACL-treated CRF rats. Additionally, the NACT-treated CRF group showed less tubulointerstitial damage than the NACL-treated CRF group. The expression and immunoreactivity of NHE3 in the kidney in the NACT-treated CRF group were lower than those in the NACL-treated CRF group. We observed that dietary NACT as alkali therapy in CRF might improve the altered saltsensitivity and ameliorate the progression of kidney injury compared to the NACL diet, which may be related to reduced renal NHE3 expression.