Effects of Glucose,Pyruvate and α-Ketoglutarate on Acetate Metabolism In Rat Mammary Gland. ∗

Summary

Glucose and pyruvate stimulate the incorporation of acetate-2-C¹⁴ into fatty acids in mammary gland slices from pregnant, lactating and postlactating rats, α-ketoglutarate did so only in tissue from pregnant and lactating animals. The effect of the 3 added substrates varied with the functional state of of the gland, being most pronounced in lactating tissue. In mammary glands from lactating and pregnant rats pyruvate inhibited glucose uptake by the tissue and the glucose stimulation of fatty acid synthesis from acetate-2-C¹⁴. In postlactating tissue pyruvate neither inhibited glucose uptake nor antagonized the glucose effect on fatty acid synthesis. On the contrary, the effect of glucose and pyruvate was additive, α-ketoglutarate did not interfere with glucose metabolism.