Effect of certain fatty acids on excretion of endogenous cholesterol

Twenty-two grams of cholesterol-free diet containing 2 gm of saturated or unsaturated fatty acid was fed to 10 female rats every 2 days. The endogenous cholesterol elimination during oleic and linoleic acid dietary periods were the same as during the fat-free cholesterol-free dietary period. During the palmitic and stearic-acid dietary periods, the endogenous cholesterol elimination increased threefold. The mechanisms involved in cholesterol reabsorption are discussed.

Effects of fatty acid anions on the electroencephalogram of unanesthetized rabbits

The i.v. injection of 4 mm/kg of buffered fatty acid anions of propionate, butyrate, valerate and caproate evoked electroencephalographic (slow high amplitude waves) and behavioral signs of sleep. The long chain fatty acid compounds were more effective than the short. On the other hand, comparable solutions of glucose, NaCl, lactate, acetone and Beta-hydroxybutyrate had no such effect. The evidence indicates that the fatty acid anion effect is mediated through the central nervous system and is not a secondary result of changes in cardiovascular physiology. CNS stimulation with amphetamine sulfate does not alter the depressant effect of the fatty acid anions.

Respiration of mycobacterium tuberculosis, strain BCG, in the presence of short chain fatty acids

Rates of oxygen consumption by washed suspensions of Mycobacterium tuberculosis, var. bovis, strain BCG, in the presence of short chain fatty acids and other substrates have been studied. Whereas the presence of acetate, butyrate, and hexanoate leads to increased but constant rates of respiration, that of propionate, pentanoate, and heptanoate leads to increased rates of respiration that diminish markedly with time. Admixture of glucose or glycerol with short chain even-numbered fatty acids gives additive rates of oxygen consumption. Admixture, however, of glucose or glycerol with odd-numbered short chain fatty acids prevents the fall off in respiration and leads to increased and constant rates of oxygen utilization. These effects of glucose or glycerol arc not due to the formation of fumarate or malate or of pyruvate or acetate. Mixtures of odd-numbered and even-numbered short chain fatty acids give rates of respiration which are (with the exception of acetate) those of the odd-numbered fatty acids alone. Acetoacetate and β-hydroxybutyrate resemble the short chain even-numbered fatty acids in this respect.