A. Baird Hastings

Improved Fixation for Histological Demonstration of Glycogen and Comparison with Chemical Determination in Liver.

Summary Glycogen of rat liver was well preserved throughout histological blocks and was not displaced in the cells when pieces of liver were fixed in ice-cold picro-alcohol-formalin. After fixation, liver sections were stained by the Bauer-Feulgen method and the optical density of each section was measured on a Photovolt electronic photometer. Chemical determinations were made of the glycogen contained in other pieces of the same livers. The livers of rats undergoing progressive starvation from 6 to 48 hours showed good correlation between the chemically and histologically determined glycogen concentrations.

Substrate concentration and metabolic pathways in liver slices in vitro

Abstract To compare the quantitative metabolic pathways followed by substrates as a function of their concentration, liver slices from fed rats were incubated with 0.3 or 1 mM, and 20 or 40 mM concentrations of 14 C-labeled galactose, fructose, mannose, glycerol and pyruvate. In qualitative terms the patterns proved similar at the low and high concentrations, but there were differences which necessitate the consideration of substrate concentration in the quantitative evaluation of the metabolism of liver.

Pyocyanin and metabolic pathways in liver slices in vitro

Abstract The effect of pyocyanin, an oxidation-reduction mediator, on the metabolism of 14 C-labeled mannose, fructose, glycerol, pyruvate, acetate, propionate, butyrate, and CO 2 in rat-liver slices has been studied. In general, pyocyanin markedly increased the oxidation to CO 2 of those substrates expected to be metabolized significantly via the phosphogluconate pathway. However, while fructose and glycerol are presumed to enter the Embden-Meyerhof pathway at the triose level, glycerol but not fructose oxidation to CO 2 was increased by pyocyanin addition. Pyocyanin decreased the incorporation of the labeled substrates into glycogen and fatty acids and also the oxidation of pyruvate, acetate, propionate, and butyrate to CO 2 . Pyocyanin thus appears to have effects on pathways in addition to the phosphogluconate pathway.

Inhibitory Effects of Pteroyl Glutamic Acid Preparations.

Summary 1. Freshly recrystallized pteroyl glutamic acid (PGA)R even in very high concentrations exerts no significant inhibitory effect on the metabolism of brain cell suspensions. 2. PGA preparations, not freshly recrystallized, have a marked inhibitory action in high concentrations (25 millimolar). In lower concentrations (1 millimolar), the inhibition is negligible. 3. The inhibitory action with pyruvate as substrate can be largely accounted for by the photofission product of PGA (2-amino-4-hy-droxy-6-formyl-pteridine).

Intracellular Potassium Concentration in Normal and Diabetic Rat Liver.

Summary The intracellular potassium concentration was found to be normal in diabetic rat liver.

1 THE CLASSIC: The State of Calcium in the Fluids of the Body

Franklin C. McLean (1899–1968) was the doyen of calcium and bone researchers in the United States and the world during the period from 1947 to 1967. He was Professor of Medicine, Dean of the Medical School at the University of Chicago and the full-time innovator of academic medicine in America during the 1930s. The coauthor, A. B. Hastings, emeritus Professor of Physiological Chemistry at Harvard University, is now living at La Jolla, Calif.