CARBOHYDRATE UTILIZATION BY CHICK EMBRYONIC HEART CULTURES

Abstract
Freshly explanted chick embryonic heart fragments were cultivated in completely synthetic media. Survival of such cultures in the complete medium, containing glucose, was established at approximately 35 to 40 days, while in the absence of carbohydrate the cultures died within 3 to 5 days. Survival was considered to be a more physiological measurement than rapid cell multiplication for normal tissues and was adopted as the criterion for all experiments reported. Fifty-two compounds were tested for their ability to replace glucose, as the sole carbohydrate, in this system. Of these, seven (mannose, fructose, galactose, β-glucose, maltose, glucose-1-phosphate, and glucose-6-phosphate) replaced glucose completely. Five others (sorbitol, alpha-methyl-D-glucoside, turanose, dextrin, and fructose-6-phosphate) were partially active. The remainder were negative. Comparison is made of the present results with those obtained by other workers using malignant cells in the presence of serum–enzymes. The present results suggest that the ability to replace glucose decreases progressively as compounds down the Embden–Meyerhof pathway are tested.