Hormonal effects on kallikrein, esterase A2, and their inhibitors in rat urine.

The effects of various hormones on the urinary excretion of kallikrein and esterase A2 were studied in rats. Chronic treatment with antidiuretic hormone had no effect on the excretion of either enzyme. Deoxycorticosterone treatment or a low sodium diet stimulated urinary kallikrein excretion (as is well known), but had no effect on urinary esterase A2. Dexamethasone markedly suppressed the excretion of both kallikrein and esterase A2 and increased the excretion of proteins (inhibitors) that bind to each of these enzymes. It is likely that the suppressive effect of glucocorticoid on urinary kallikrein and esterase A2 activities is due to the increase in urinary binding proteins. There is also a strong correlation between the excretion of kallikrein and esterase A2 in normal untreated rats. Such a correlation might arise from a common effect of glucocorticoid-influenced inhibitors on both enzymes.