S100A6 and essential hypertension: The mean PAC (ng/dl), PRA (ng/ml/h), and ARR (ng/dl per ng/ml/h) levels were 36.9 ± 29.0, 2.1 ± 2.1, and 222.8 ± 622.4 in group 1 and 54.4 ± 39.6, 0.9 ± 4.0, and 527.1 ± 1,533.4 in group 2, respectively, with a significantly lower PAC level in the essential hypertension group than that in the PA group (P = 0.009).