Masahide Yasuda

Effects of 4-pentenoic acid and furosemide on renal functions and renal uptake of individual free fatty acids

Abstract1.Effects of 4-pentenoic acid (4-PA), an inhibitor of fatty acid oxidation, on renal function and on renal uptake of individual free fatty acids (FFA) were investigated using mongrel dogs, and the results compared with findings in the case of furosemide.2.Continuous infusion of 4-PA at a rate of 0.66 μmoles/kg · min into the renal artery resulted in a marked reduction of glomerular filtration rate after 45 min. Sodium reabsorption rate tended to decrease at 30 min and a significant decrease was seen after 45 min. With decrease in the renal sodium reabsorption rate, the urine flow increased about 3 times, and there was a marked natriuresis.3.Concentrations of individual FFA in the arterial and renal venous plasma were determined by gas-liquid chromatographic analysis. In the control period, data from 25 dogs showed renal uptake of palmitic, stearic, olcie, and cinoleic acids to be approximately 40, 15, 25, and 10 nmoles/g · min, respectively, and the uptake of palmitic and oleic acids was depressed during the natriuresis following administration of 4-PA and furosemide.4.These results suggest that fatty acids play an important role in the energy supply in renal tubular sodium transport.

Effects of linoleic acid hydroperoxide on the formation of lipid peroxide in the rat liver mitochondria

An in vivo study was made on the effect of linoleic acid hydroperoxide on the formation of lipid peroxide in rat liver mitochondria, and results are as follows: There were no changes in contents of lipid peroxide and total sulfhydryl in rat liver mitochondria after daily administration of linoleic acid hydroperoxide (10 mg/kg, i.p.) for 3 or 7 days. Changes in the fatty acid composition in plasma and liver after i.p. administration of linoleic acid hydroperoxide for one week were not observed as compared to that of control animals. In addition, no appreciable change was found in the fatty acid composition of phosphatidylserine and phosphatidylinositol in liver mitochondria from rats treated with linoleic acid hydroperoxide. After treatment with linoleic acid hydroperoxide for 3 days, content of plasma triglycerides increased, but no effect was observed in liver triglycerides. However, plasma triglycerides returned to the control level and triglycerides in liver increased by treatment with linoleic acid hydroperoxide for one week. Free fatty acids decreased in plasma but not in the liver from rats treated with linoleic acid hydroperoxide for 3 or 7 days.