GENDER-RELATED MAGNESIUM URINARY EXCRETION IN RATS: INFLUENCE OF FUROSEMIDE

Several experimental studies showed gender-related differences in ion transport across cell mem- brane and ion excretion with urine. The aim of the present study was to define 24-h urinary magnesium (Mg) excretion and the influence of furosemide (FUR) on gender-related differences in Mg excretion in adult Wistar rats. 24-h urinary Mg, sodium, chloride, creatinine and pH levels were measured. Control groups of intact female (n=10) and intact male (n=10) rats, as well as female (n=6) and male (n=6) rat groups after a single intraperitoneal administration of 10 mg/kg FUR were examined. No gender-related differences of 24-h Mg uri- nary excretion, urinary Mg excretion per 100 g of body weight, urinary pH diuresis were found in control rat groups. The 24-h natriuretic (0.395 ± 0.06 mmol/100 g vs 0.243 ± 0.08 mmol/100 g; p < 0.05), chloriuretic (0.747 ± 0.08 mmol/100 g vs 0.518 ± 0.12 mmol/100 g; p < 0.05) and diuretic (20.2 ± 3.4 ml vs 14.8 ± 4.2 ml; p < 0.05) response after administration of FUR in female rats were significantly higher than in male rats. Urinary Mg excretion per 100 g of body weight after administration of FUR in female rats was significantly higher than in male animals (0.03090 ± 0.006 mmol/ 0.006 mmol/100 g vs 0.0184 ± 0.004 mmol/100 g, p < 0.05). FUR, alongside Na, K and Cl excretion with urine, evokes also a magnesiuric effect with a significant gender difference; the mechanism of such concomitant effect is not yet clear.