Effect of different linoleic acid intakes on prostaglandin biosynthesis and kidney function in man

Prostaglandin (PG) biosynthesis and kidney function was investigated in 24 adults (23 to 32 yr) during isocaloric formula diet periods, for 2 wk each, providing a linoleic acid supply of 0, 3, 3.5, 4, 6, 8, 13, 17, 18, or 20% of total energy intake. Total protein intake (15 energy %) was constant, as well as 5 g NaCl, 3 g KCl, and 0.6 g cholesterol per 2200 kcal formula diet. The amount of PG metabolites, PG-E, sodium, and creatinine in 24-h urine increased with augmented linoleic acid intake. Comparing a linoleic acid intake of 0 and 20 energy %, an increase of sodium (8%) and creatinine (16%) in 24-h urine was found on the 5th day of high linoleic acid supply. Coincidently a stimulated PG biosynthesis could be measured. Potassium, water, and PG-F excretion showed no relation to linoleic acid intake. It is concluded that linoleic acid in the diet stimulates PG-E biosynthesis in man, leading to effects in systems which control renal function, and may have clinical relevance for the sodium and potassium balance in man.