Increased urinary excretion of angiotensin during anaphylactoid reactions

Immunoreactive angiotensin I (ANG I) and angiotensin II (ANG II) were measured in human urine, after purification on octadecasilyl-silica cartridges.The total daily excretion of ANG I and II in healthy volunteers was 292.2±62.5 and 12.2±2.5 pmol/24 h (mean±SEM; n = 14). No differences in the concentrations of ANG I or II were detected between females and males. Although lower levels of ANG I and II were found during the nighttime, no clear-cut circadian rhythm in the excretion of the peptides was found. ANG II was not degraded in acidified urine which shows the effective inhibition of ANG-II-degegrading enzymes. Oral provocation tests (OPT) in patients with a history of anaphylactoid reactions (AR) to drugs, foods and food additives were associated with elevated ANG I and II concentrations when symptoms of anaphylaxis occurred. The excretion of ANG I increased by a factor of 7.8±2.4 and the excretion of ANG II by a factor of 6.1 ± 1.6 (mean±SEM; n = 15). In patients with negative OPT and no clinical symptoms of anaphylaxis, the levels of ANG I and II remained unchanged (n = 26). It is concluded that angiotensin peptides play a role during the events of AR. The peptides may be considered as counteracting factors which stabilize cardiovascular functions.