Human urine samples, purified on
octadecasilyl-silica cartridges, contained immunoreactive
angiotensin I, II,
arginine vasopressin and
oxytocin. The daily excretion of these
peptides in healthy volunteers was 190.00 +/- 38.43 (n = 12), 17.48 +/- 3.09 (n = 12), 63.43 +/- 14.84 (n = 8) and 13.52 +/- 1.42 (n = 7) pmol/24 hr, respectively (mean +/- s.e.m.). Patients with a history of
anaphylactoid reactions to drugs or
food additives showed clinical symptoms such as
urticaria, flush,
nausea,
dizziness and
hypotension after oral provocation with cyanocobalamine,
propyphenazone,
acetylsalicylic acid and
sodium benzoate. In five of the seven patients,
angiotensin I and II were increased several fold in the urine fractions after symptoms were reported. The average increase in the urine concentration of both
peptides was fourfold and 5.5-fold. In three out of five patients, the mean excretion of
arginine vasopressin and
oxytocin immunoreactive material was also elevated by
a factor of 5.7 and 4.4, respectively. Oral provocation with a placebo failed to elicit anaphylactoid symptoms or an increase in the urine levels of
angiotensin I or
angiotensin II.
Angiotensin I and
angiotensin II-like immunoreactivity could be characterized on HPLC as Ile5-angiotensin I, Ile5-angiotensin II and
angiotensin II metabolites. HPLC characterization of immunoreactive
arginine vasopressin and
oxytocin in two different gradient systems showed retention times different than the retention times of the corresponding synthetic standard
peptides indicating that both
peptides are not authentic AVP and OXT. These results suggest that
angiotensin I and
angiotensin II may be involved in the clinical events observed during some forms of
anaphylactoid reactions.