ZINC, COPPER, AND ZINC-DEPENDENT OR COPPER-DEPENDENT ENZYMES IN HUMANHYPERTENSION

Imbalance of zinc and copper status has been hypothesized in human hyp ertension. A ease-control study was carried out to elucidate the possi ble relationship between zinc and copper status and essential hyperten sion. Thirty-one subjects affected by mild stable hypertension, pharma cologically untreated, were investigated together with 31 normotensive controls individually matched for sex, age, and smoking habits. Zinc and copper in serum and urine were measured, and serum activities of a lkaline phosphatase (AP), lactic dehydrogenase (LDH), copper-zinc supe roxide dismutase (Cu-Zn SOD), lysyl oxidase (LOX), and monoamine oxida se (MAO) were evaluated. No significant difference in serum and urine zinc and copper content as far as in serum activity of zinc (AP and LD H) or copper (Cu-Zn SOD, LOX, and MAO)-dependent enzymes was found bet ween hypertensives and normotensives. Positive relationships were foun d in normotensives between serum and urine levels of zinc (r = 0.577; p = 0.001) and copper (r = 0.394; p = 0.028), and between serum copper and Cu-Zn SOD (r = 0.534; p = 0.002). In normotensives, diastolic blo od pressure and serum zinc were positively related (r = 0.370; p = 0.0 41). In hypertensives, inverse correlations were observed between dias tolic blood pressure and AP (r = -0.498; p = 0.004) and Cu-Zn SOD (r = -0.452; p = 0.011), and between systolic blood pressure and LOX (r = -0.385 p = 0.033). Diastolic blood pressure was related to LDH inverse ly in hypertensives (r = -0.357; p = 0.049) and positively in normoten sives (r = 0.457; p = 0.010). In normotensives, diastolic blood pressu re was inversely related with MAO (r = -0.360; p = 0.046). These findi ngs support the hypothesis that an imbalance of zinc and copper status might he involved in human hypertension.