Sidney D. Kobernick

Effect of physical activity on cholesterol atherosclerosis in rabbits.

Summary 1. Thirty-six New Zealand white rabbits of 5 litters and one group of miscellaneous rabbits were fed 28 g of cholesterol for 60 days. Half of the animals were exercised for 10 minutes a day; half the animals remained sedentary. 2. There was a significant diminution of atherosclerosis in the exercised animals as determined by visual grading and by chemical analysis of the lipid content of the aorta.

ENZYME HISTOCHEMISTRY OF RABBIT AORTA, IN SPONTANEOUS LESIONS AND AFTER ACUTE EXERCISE.

Summary 1. The activities of succinic dehydrogenase, nonspecific esterase, cholinesterase, glucose-6-phosphatase, alkaline phosphatase, cytochrome oxidase, DPN diaphorase, TPN diaphorase, phosphorylase and leucine aminopeptidase in the frozen sections of adrenal, liver, kidney, lung, spleen, pancreas, heart, striated muscle, small arteries and aorta of acutely exercised and sedentary rabbits were studied histochemically. 2. There were no enzymatic changes attributable to the acute exercise in any organs. 3. TPN diaphorase is present in the intima, medial muscle fibers and adventitia of the aorta. 4. Phophorylase is present in the medial muscle fibers of the aorta. 5. Leucine aminopeptidase is absent in all parts of the aorta. 6. In the spontaneous lesions, TPN diaphorase and phosphorylase are decreased as the medial muscle fibers are degenerated.

Effect of Butter Fat and Body Weight on Experimental Atherosclerosis in Rabbits.

Summary and conclusions 1. Rabbits were fed cholesterol, butter, and ad libitum Purina chow diets in various amounts and combinations to evaluate the effect of butter fat and body weight on serum lipids and experimental atherosclerosis. 2. 0.25 gram of butter per day had no effect on serum lipid levels nor did it produce aortic atheromata, whereas an equal amount of cholesterol produced definite increases in serum lipids and atheromatous plaques. 3. When 10 g of butter were given per day, there was a small but significant rise in all lipid fractions. 4. On the group level, a close correlation was found between severity of aortic lesions and degree of hyperlipemia, which in turn was related to total cholesterol intake. In individual animals considerable variation was encountered. 5. No differences were observed in initial weights or average weight gains. 6. Increased caloric intake in the form of ad libitum stock diets did not augment the cholesterol-induced hyperlipemia nor increase the severity of atherosclerosis in rabbits. 7. We may conclude from this study that saturated fats in the diet are not a major factor in the pathogenesis of experimental atherosclerosis in rabbits.