title: Measurement of 8-arginine-vasopressin by radioimmunoassay. Development and application to urine and plasma samples using one extraction method.
abstract: This paper describes the production and evaluation of an antiserum with high affinity (Ka = 1.9 X 10(11) l/mol) and specifity to 8-arginine-vasopressin (AVP). The antiserum binds only to the intact and unchanged ring and tail of the AVP-molecule. AVP was labelled with 125I by a modification of the chloramin T method and purified by gel-filtration. We describe the development and validation of a radioimmunoassay for AVP in human plasma and urine, using only one extraction method (octa-decasilyl-treated silica microcolumns) for both biological fluids. The overall sensitivity of the assay method is 0.3 pg/ml plasma and 0.6 pg/ml urine. Mean (+/- SD) plasma AVP-concentration in normally hydrated females was 1.2 +/- 0.6 pg/ml (median 1.2 pg/ml) and 1.7 +/- 0.7 pg/ml (median 1.8 pg/ml) in males. Mean urinary AVP excretion was 73 +/- 43 ng/day with ad libitum water intake and normal activity. Sex differences were not statistically significant. We also assessed the response of plasma AVP and urinary AVP-excretion to waterload and dehydration.
mesh_terms: D000328:Adult; D001127:Arginine Vasopressin / Q000032:analysis* / Q000097:blood / Q000276:immunology / Q000652:urine; D002850:Chromatography, Gel; D003429:Cross Reactions; D005260:Female; D006801:Humans; D007106:Immune Sera; D008297:Male; D008875:Middle Aged; D010455:Peptides / Q000276:immunology; D011863:Radioimmunoassay / Q000379:methods*; D012016:Reference Values; D013894:Thirst; D014867:Water / Q000008:administration & dosage
chemical_list: D007106:Immune Sera; D010455:Peptides; D014867:Water; D001127:Arginine Vasopressin