Radioenzymatic assay of catecholamines in plasma after a preliminary solvent extraction compared with an analogous liquid-chromatographic method.
Catechol-borate complexation and ion-pair formation combined with organic solvent extraction as preliminaries to radioenzymatic assay (REA) with catechol-O-methyltransferase-catalyzed methylation allows the quantification of catecholamines in plasma samples of any volume. We attained improved detection limits for 1-mL samples: 9 ng/L for norepinephrine (NE), 8 ng/L for epinephrine (E), and 11 ng/L for dopamine (DA). Precision data resemble those obtained by REA for small-volume samples. Comparison with a liquid chromatography-electrochemical detection (LCEC) technique showed the two methods to be equivalent for NE and E determinations, but DA estimations were lower by REA than by LCEC.
Feoli
J
J
Fondation de Recherche en Hormonologie, Fresnes, France.
Bijault
C
C
Dehennin
L
L
D000818:Animals; D002021:Buffers; D002394:Catechol O-Methyltransferase / Q000378:metabolism*; D002395:Catecholamines / Q000097:blood*; D002851:Chromatography, High Pressure Liquid; D002853:Chromatography, Liquid; D004298:Dopamine / Q000097:blood; D004837:Epinephrine / Q000097:blood; D005780:Gelatin; D006801:Humans; D008676:Metanephrine / Q000378:metabolism; D008745:Methylation; D009638:Norepinephrine / Q000097:blood; D010710:Phosphates; D000091402:Prohibitins; D051381:Rats; D012997:Solvents; D014316:Tritium
D002021:Buffers; D002395:Catecholamines; C000717331:PHB2 protein, human; D010710:Phosphates; D000091402:Prohibitins; D012997:Solvents; D014316:Tritium; D008676:Metanephrine; D005780:Gelatin; D002394:Catechol O-Methyltransferase; D004298:Dopamine; D009638:Norepinephrine; D004837:Epinephrine