Samuel M. Greenberg

The action of chlorpromazine on yeast hexokinase

Abstract The effect of chlorpromazine on yeast hexokinase was investigated in a reaction system in which the activity of the kinase enzyme, coupled to glucose-6-phosphate dehydrogenase, was determined by measuring spectrophotometrically the reduction of TPN. Hexokinase activity, either in the presence or absence of chlorpromazine, showed great sensitivity to the magnesium-ATP ratio. Concentrations of chlorpromazine from 8·5 × 10−6M to 6·8 × 10−5 M either greatly activated or inhibited hexokinase activity, depending on the level of magnesium-ATP in the system. Implications of the observed effects of CPZ on hexokinase are discussed in relation to some of the pharmacological activities of the drug.

The effect of chlorpromazine hydrochloride on glutamic acid decarboxylase and pyridoxal kinase in rat brain homogenates.

Abstract The effect of the in vivo administration of chlorpromazine hydrochloride on glutamicacid decarboxylase and pyridoxal kinase activity was investigated in brain homogenates from normal and vitamin B 6 -deficient rats. Chlorpromazine had little or no direct effect on rat brain glutamic acid decarboxylase activity, but was found to be a potent inhibitor of rat brain pyridoxal kinase activity. Pyridoxal kinase in brain homogenates from vitamin B 6 -deficient rats showed greater susceptibility to inhibition by chlorpromazine than did pyridoxal kinase from rats on a complete diet.

Hypocholesteremic Effect of β-Diethylaminoethyl Diphenylpropylacetate Hydrochloride (SKF No. 525-A) in the Dog

Summary β-Diethylaminoethyl diphenylpropylacetate hydrochloride (SKF No. 525-A) reduced significantly plasma total cholesterol and aortic cholesterol in dogs. Chronic daily administration of the SKF No. 525-A to dogs for 5 months resulted in marked fatty infiltration of the liver, which was rapidly reversible upon withdrawal of the compound.

Enhancement of Growth of Vit. B6-Deficient Rats by Chlorpromazine Hydrochloride (SKF No. 2601-A)

Summary At very low dietary levels, chlorpromazine has a favorable effect on growth and metabolism of Vit. B6-deficient rats. These animals gained more weight, had more nearly normal organ weights, and excreted less creatine and phosphates than did the pyridoxine-deficient controls.

The Antihypercholesteremic Effect of Essential Fatty Acids in Hypercholesteremic Dogs

E. J. VAN LooN, PH.D. H ANSEN and Wiese’ demonstrated the dog’s need for dietary unsaturated fats. These same investigators2 showed serum cholesterol values were lower in dogs fed unsaturated fatty acids than in dogs fed butter. Tsai et ‘ reported later serum cholesterol values were lower in dogs fed vegetable oils. The availability of naturally hypercholesteremic dogs afforded us an opportunity to study, under natural dietary conditions, the antihypercholesteremic effects of unsaturated fatty acids and of vegetable oils.