Effects of thyroxine and dexamethasone on kinetic characteristics of the small intestine enzymes in rat pups following a low-protein diet in female rats during lactation

It is shown, that the value of Km for maltase, alkaline phosphatase, aminopeptidase M and glycyl-L-leucinedipeptidase, prepared from the jejunum and ileum of 10-day rat litter in membrane and soluble forms in most cases differed but a little in control animals and the rat litter whose mothers in the period of lactation had a diet with 2.5-fold reduced content of protein, and did not change under action of injected thyroxin and dexamethasone. It may be assumed that in the given experimental conditions each of the investigated digestive hydrolases in membrane and soluble forms represents the same enzyme. In conditions of the protein insufficiency in lactating females diet and under action of exogene hormones, apparently, no significant changes occur in structure of synthesised enzymes.