Laboratory procedures
For bradykinin measurements, blood was collected into polypropylene tubes containing chilled ethanol and let the mixture stand for 30 min at 4 °C. Samples were then centrifuged and the supernatant was stored frozen at -80 until processing. Bradykinin was measured by high-perfomance liquid chromatography (HPLC) following by electrospray inoisation mass spectrometry (ESI-MS) as previously described [