Benidipine attenuates glomerular hypertension and reduces albuminuria in patients with metabolic syndrome

Recent studies have shown that metabolic syndrome is associated with an increased risk for chronic kidney disease. We recently found that the prevalence of sodium-sensitive hypertension in patients with metabolic syndrome was significantly higher than that in patients with essential hypertension but without metabolic syndrome. We therefore assessed the effects of benidipine, a long-acting calcium channel blocker, on the sodium sensitivity of blood pressure and renal hemodymarnics in 5 patients with metabolic syndrome. Glomerular hemodynamics were assessed using pressure-natriuresis curves, which were constructed by plotting the urinary excretion of sodium as a function of the mean arterial pressure, which was calculated as the mean of 48 values based on 24-h monitoring, during the intake of low (3 g NaCl daily) and relatively high (10 g NaCl daily) sodium diets. Under the relatively high sodium diet condition, benidipine significantly lowered systolic and diastolic blood pressure. The pressure-natriuresis curve was steeper after the administration of benidipine. Benidipine lowered glomerular capillary hydraulic pressure (P-GC) levels (from 54.4 +/- 7.5 to 47.0 +/- 7.0 mmHg, p=0.0152) and reduced both the resistance of the afferent arterioles (from 10,338 +/- 2,618 to 9,026 +/- 2,627 dyn.s/cm(5), p=0.047) and the resistance of the efferent arterioles (from 4,649 +/- 2,039 to 2,419 +/- 2,081 dyn.s/cm(5), p=0.003). The urinary albumin excretion rate also decreased after the administration of benidipine. These findings indicated that benidipine may be effective for reducing the risk of developing chronic kidney disease in patients with metabolic syndrome.