Reversed-phase HPLC separation of plasma norepinephrine, epinephrine, and dopamine, with three-electrode coulometric detection.

Abstract

We present a method involving minor modifications of previous techniques, in which we use an ion-pair reversed-phase HPLC separation with three-electrode coulometry. Isocratic baseline separations can be obtained in 5 min. The sample preparation procedure, involving extraction with alumina at low temperature, allows good reproducibility (within-run and between-run CVs less than 10%) and improved sensitivity (less than 5 pg of each catecholamine per extract). This method allows approximately 70 low-cost plasma catecholamine analyses to be done in a working day.

Non‐alpha‐adrenergic effects on systemic vascular conductance during lower‐body negative pressure, static exercise and muscle metaboreflex activation

“…Circulating levels of NE and adrenaline (EPI) were measured from venous blood samples drawn via the antecubital vein after 4 min of each phase; this was accomplished successfully in eleven subjects (Musso et al . ). With the given accuracy of the analysis of EPI, concentrations < 0.1 n m could not be quantified.…”

Exercise induces excessive normetanephrine responses in hypertensive diabetic patients

“…The intraassay coefficients of variation (CV) were < 5% (normetanephrine) and 7% (metanephrine), interassay CVs were < 12·5%. Plasma catecholamines were analyzed by reverse-phase HPLC [15] using plasma extraction tubes (ESA, Bedford, MA) for the isolation procedure [14]. Interassay and intraassay CVs were < 5% for both compounds.…”

α-Adrenergic effects on low-frequency oscillations in blood pressure and R-R intervals during sympathetic activation

“…Blood pressure was also measured manually to validate the BP measured from finger plethysmography. Venous blood samples were drawn from the antecubital vein after 4 min of each phase for subsequent analysis of circulating levels of NA (Musso et al 1989).…”