A lipolytic factor from the submaxillary salivary glands of the rat

In 1978 it was observed that an aqueous extract of the submaxillary salivary glands of rats contained a protein substance which was able in vitro to mobilize free fatty acids and glycerol from the adipose tissue of rat epididymis. Using a Sephadex G-100 column it was possible to demonstrate in the aqueous extract of rat submaxillary salivary glands three protein fractions with molecular weights 72 000 D, 52 000 D and 14 000 D. Each of these fractions could stimulate lipolysis and the optimal protein concentration in the incubation fluid was 10(-6)M. In an alkaline medium the protein fractions exerted a greater lipolytic effect. In relation to adrenaline, ACTH, glucagon, the lipolytic effect of the studied fractions was about 30% lower.