Natriuresis and Carbohydrate-Induced Antinatriuresis in Fasted, Hydrated Hypertensives

Summary After an overnight fast and oral hydration with water, hypertensive subjects developed a significant natriuresis (mean urine sodium excretions increased from 130 to 291 μeq/min). The incidence of a natriuresis (>200 μeq sodium excreted per minute) was 75% in the hypertensive group (16 subjects) compared to 27% in a previously studied normotensive group (22 subjects). The incidence of a carbohydrate-induced antinatriuresis (>30% decrease in urinary sodium excretion) was 62% in the hypertensive group compared to 41% in the normotensive group. No decrease in plasma volume (131I-labeled albumin concentration) due to a shift of solute and water intracellularly could be documented to explain the antinatriuretic effect of glucose. An incidental observation was a significant decrease in plasma zinc concentrations after glucose ingestion. The authors acknowledge the technical assistance of Mr. Carl Haygood, Mr. Howard Guiles, Mrs. Dorothy Shirey, Mrs. Norma Luster, and Mrs. Dee Hammarsten and the nursing assistance of Mrs. Fern Brandt, R.N.