R. K. Boutwell

Effect of Flavor on Nutritive Value of Fats.

Summary With ad libitum feeding and with lactose as the sole carbohydrate, the growth and appearance of albino male rats fed butter fat was superior to that of animals fed corn oil. Removal of the flavoring agents from butter fat by chromatographing or the addition of one such agent, diacetyl, to corn oil had little effect on the comparative nutritive value of the two fats. Rats fed butter fat or corn oil on rations containing dextrose as the sole carbohydrate grew at equal rates and were of normal appearance. Flavor played no part in these dextrose experiments.

Production of acrodynia in mice fed diets low in pyridoxine.

Summary 1. Pyridoxine deficiency was produced in weanling male and in young adult female mice fed (a) a purified diet containing 9 other crystalline B vitamins, and (b) a semi-purified diet containing a low level of liver powder. 2. Acrodynia appeared among both the weanling and young adult mice fed these 2 diets. 3. As little as 0.166 mg of added crystalline pyridoxine-HCl per kg of the purified diet protected the mice from acrodynia and resulted in a good growth response by the weanling mice.

The acute effect of cortisone treatment on the utilization of glucose by the mouse

Abstract 1. 1. The specific activity-time curves of blood glucose and respiratory CO 2 were determined in normal and cortisone-treated mice after a single intravenous injection of radioactive glucose. Measurements were made 4–6 hr. after the injection of a large dose of cortisone. The rationale of the study of the early effects of cortisone in contrast to the chronic picture was presented. 2. 2. Within 4–6 hr. after treatment with cortisone, the turnover time of glucose was extended by 50%. The amount of glucose utilized by the treated mice was calculated to be 65% of normal. 3. 3. The reduction in glucose utilization was attributed to a depression in glucose oxidation as well as in the quantity of glucose lost to other metabolic pools.

Influence of in vivo administration of adrenocorticoids on metabolism of thymus, liver and tumor tissues.

Summary In cell suspensions of thymus or lymphatic tumor tissues from rats treated 4 to 24 hours previously with cortisone or hydrocortisone consistent decreases in C14O2 production and in incorporation of C14 into tissue protein were demonstrated whether incubations were conducted in the presence of uniformly labeled glucose or fructose, acetate-1-C14 or glycine-2-C14. Liver tissue exhibited increased in vitro accumulation of C14 into glycogen after hormone treatment. A variety of other metabolic pools showed no difference in total C14 accumulation or distribution resulting from hormone administration. Methods of analysis for a wide spectrum of metabolites from tissue incubates are outlined. Dinitrophenol, methylene blue, and brilliant cresyl blue increased the level of hepatic glycogen in rats when administered at the beginning of a 28-hour fast period. These increments are in addition to the increase caused by the cortical hormones and may represent a failure to utilize the glycogen during the fast.

Effect of Puromycin on Hepatic Glycogen Phosphorylase Activity.

Summary Liver glycogen phosphorylase activity was studied in mice at early times subsequent to in vivo administration of puromycin, and following puromycin addition to incubations of rat liver slices. No effect of puromycin on phosphorylase could be detected following injection of unanesthetized mice. Puromycin treatment of pentobarbital-anesthetized mice, however, resulted in an enhancement of the phosphorylase activity as compared to control values. Phosphorylase activity in rat liver slices incubated with puromycin was greater than those incubated without puromycin. These results indicate that puromycin can elevate liver phosphorylase activity, a finding consistent with the hepatic glycogenolytic action of the antibiotic in vivo.