Validation of a radioimmunoassay for the determination of total corticosterone in rat plasma

Citation
Tkh. Pedersen et al., Validation of a radioimmunoassay for the determination of total corticosterone in rat plasma, ANALYT CHIM, 413(1-2), 2000, pp. 63-69
Citations number
27
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Spectroscopy /Instrumentation/Analytical Sciences
Journal title
ANALYTICA CHIMICA ACTA
ISSN journal
0003-2670 → ACNP
Volume
413
Issue
1-2
Year of publication
2000
Pages
63 - 69
Database
ISI
SICI code
0003-2670(20000518)413:1-2<63:VOARFT>2.0.ZU;2-0
Abstract
A radioimmunoassay (RTA) for total corticosterone (CORT) in rat plasma requ iring a plasma volume of 2 mu l was established. The importance of inactiva ting plasma corticosteroid-binding globulin (CBG), denatured by heat, befor e measuring CORT was shown. The method was evaluated and shown to be within analytical and statistical controls, with a recovery not significantly dif ferent from 100%. The limit of detection OLD) was 0.2 mu g dl(-1). Intra-as say coefficients of variation (CVs) were 7.2% for plasma samples at 33.5 mu g dl(-1) CORT (n=10) and 8.5% at 0.75 mu g dl(-1) CORT (n=18). Inter-assay CVs were 6.8% at 23.1 mu g dl(-1) CORT (n=8) and 5.4% at 8.9 mu g dl(-1) C ORT (n=8). Validation of the method was performed using a group of male rat s (Mol:WIST Han; M & B A/S, Denmark; n=12), housed under conventional envir onmental conditions from the age of 4 weeks. The rats were 3 and 7/2 months old when they underwent the blood sampling procedure. The result showed th at the method had a capacity to detect CORT concentrations comparable with previous reported basal concentrations. Finally, the possible stress induci ng effect of the blood sampling procedure was examined using two groups of male rats housed under either conventional or enriched environmental condit ions. The result indicated that conventional environment housing induces sl ightly stressed animals compared to enriched housing. Enriched housing may provide an environment that makes it possible for rats to compensate for a stressful situation, i.e., the blood sampling procedure. (C) 2000 Elsevier Science B.V. All rights reserved.