Urinary and plasma urodilatin measured by a direct RIA using a highly specific antiserum.
Urodilatin (95-126) (URO) appears to play a major physiologic role in fluid homeostasis and produces major changes when administered intravenously. Here we describe a monospecific, high-affinity antiserum against URO with no cross-reactivity (<0.01%) against the structural highly homologous atrial natriuretic peptide 99-126 (ANP-99-126), ANP analogs, and related peptides such as brain natriuretic peptide. A competitive RIA was developed, based on this antiserum. Urine samples with or without ethanol extraction and plasma samples without pretreatment were analyzed by the RIA, which had a detection limit of 10.5 ng/L, a linear measuring range between 10.5 and 1000 ng/L, and recoveries of 93-102% in urine and 90-104% in plasma. The intraassay CVs were 8.2% and 8.1% for urine samples with 269 and 669 ng/L URO; the interassay CV was 9.7% at 839 ng/L. Using this assay, we present URO data for urine from healthy volunteers receiving low and routine sodium diets and from clinical urine specimens; we also present pharmacokinetic data for URO in plasma from patients suffering from bronchial asthma and treated by URO infusion.
Meyer
M
M
1 Niedersächsisches Institut für Peptid-Forschung GmbH (IPF), Feodor-Lynen-Strasse 31, 30625 Hannover, Germany.
Armbruster
F P
FP
Maier
I
I
Schwing
J
J
Haller
C
C
Missbichler
A
A
Adermann
K
K
Forssmann
W G
WG
Woloszczuk
W
W
D000818:Animals; D000918:Antibody Specificity; D001249:Asthma / Q000188:drug therapy / Q000378:metabolism; D009320:Atrial Natriuretic Factor / Q000032:analysis* / Q000097:blood / Q000276:immunology / Q000652:urine; D001993:Bronchodilator Agents / Q000032:analysis* / Q000097:blood / Q000276:immunology / Q000652:urine; D006328:Cardiac Catheterization; D004232:Diuretics / Q000032:analysis* / Q000097:blood / Q000276:immunology / Q000652:urine; D007106:Immune Sera; D007262:Infusions, Intravenous; D008297:Male; D010446:Peptide Fragments / Q000032:analysis* / Q000097:blood / Q000276:immunology / Q000652:urine; D011817:Rabbits; D011863:Radioimmunoassay; D012756:Sheep; D012982:Sodium, Dietary / Q000008:administration & dosage
D001993:Bronchodilator Agents; D004232:Diuretics; D007106:Immune Sera; D010446:Peptide Fragments; D012982:Sodium, Dietary; C056452:Ularitide; D009320:Atrial Natriuretic Factor