Tissue kallikreins and kinins: roles in human disease and target for new drug development.

There is no convincing evidence presently for the notion that tissue kallikrein-regulated systems are the proximate cause of any form of human or animal disease. Nevertheless, the collection of facts very briefly mentioned here, suggest strongly that all of the conditions for such a possibility are being met and the right questions about such possibilities are being asked. Even without the answers, it is quite possible to anticipate what the abnormalities might be, and try to devise rational therapeutic strategies and new drugs. This is an area of endeavor which will be worthwhile because it will allow us to learn more about how kininogens, kallikreins, kinins and kininases function, even as new therapies are created.