CHANGES IN GLUCOSE-TRANSPORT ACTIVITIES IN MAMMARY ADENOCARCINOMA OF DOGS

The activities of D-glucose transport (D-GT) and cytosolic enzymes wer e significantly higher in mammary adenocarcinoma of dogs than in mamma ry gland from normal dogs. The activities of D-GT in adenocarcinoma we re over three-and-a-half times higher than in the controls. The Km val ue of the D-GT activity for glucose in both the adenocarcinoma and nor mal mammary gland was approximately 0.9 mM. The activities of the key glycolytic enzymes, hexokinase and pyruvate kinase, in the adenocarcin oma were also more than three-and-a-half times higher than in the cont rols. The increased activities of D-GT are considered to be accompanie d by an acceleration of glucose utilisation in the adenocarcinoma of d ogs.