Potentiation by aminopeptidase P of blood pressure response to bradykinin.

We examined whether a specific aminopeptidase P (APP) inhibitor, apstatin, increases vasodepressor responses to bradykinin in anaesthetized rats, and whether it would augment blood pressure responses further after treatment with the angiotensin-converting enzyme inhibitor (ACEi), lisinopril. Apstatin doubled the maximum blood pressure response to bradykinin. The area under the curve (AUC), which incorporates both peak blood pressure changes and duration of response, was doubled in apstatin-treated rats vs controls and in the apstatin+lisinopril group vs lisinopril alone. These data demonstrate that APP is an important kinase in vivo.