 This is a randomized, double-blind cross-over study with three treatment periods consisting of 20, 40 and 60 mg lisinopril daily in random order. The endpoints of the study will be examined after each treatment period. There is no wash out between treatment periods. To minimize the risk of hypotension every treatment period starts with 20 mg lisinopril for two weeks. Thus, the risk of adverse effects is minimized and an increase in dose from 0 mg to 60 mg lisinopril is avoided. 