The objective of this project is to determine the function of kinin and angiotensin metabolizing enzymes. Kinins and angiotensins, naturally occurring agents which have significant effects on intestinal function, are both metabolized by converting enzyme. Converting enzyme is present on the lining of the intestine and may control the level of kinins and angiotensins within the gut. Captopril, taken orally, inhibits converting enzyme in the blood and may come to be used widely to treat some forms of hypertension. Inhibition of the intestinal enzyme by captopril could alter some aspects of intestinal function in addition to its effects on blood pressure. The present study will examine the distribution and subcellular localization of these enzymes including kallikrein, renin, converting enzyme, kininase, and angiotensinase in the human, swine and rat. Knowledge of the distribution and properties of these enzymes will help us to understand their function in intestinal physiology.