Simultaneous Quantification of Plasma Catecholamines and Metanephrines by LC‑MS/MS

Quantification of unconjugated metanephrines in human plasma without interference by acetaminophen.

BACKGROUND Pheochromocytoma is a rare cause of hypertension resulting from increased catecholamine secretion. We aimed to develop a method to measure unconjugated plasma normetanephrine (NMN) and metanephrine (MN) without interference from acetaminophen, a widely prescribed drug for headaches. METHODS Plasma samples were obtained from 48 subjects (23 males, 25 females; mean age, 49 +/- 14 yea...

Simultaneous liquid-chromatographic determination of plasma catecholamines and metabolites.

Featured Article: Eisenhofer G, Goldstein DS, Stull R, Keiser HR, Sunderland T, Murphy DL, Kopin IJ. Simultaneous liquid-chromatographic determination of 3,4-dihydroxyphenylglycol, catecholamines, and 3,4dihydroxyphenylalanine in plasma, and their responses to inhibition of monoamine oxidase. Clin Chem 1986;32:2030 –3. This report described a liquid chromatographic electrochemical detection (LC...

Disappearance rate of catecholamines, total metanephrines, and neuropeptide Y from the plasma of patients after resection of pheochromocytoma.

BACKGROUND Plasma free metanephrines are a more reliable analyte to measure than catecholamines for the biochemical diagnosis of pheochromocytomas. We hypothesized that the long persistence of total (sulfate-conjugated plus free) metanephrines in the blood might have a significant diagnostic value. METHODS We measured plasma concentrations of catecholamines and total metanephrines (sulfate-co...

Plasma Metanephrines in the Diagnosis of Pheochromocytoma

Urinary and Plasma Catecholamines and Metanephrines in Dogs with Pheochromocytoma, Hypercortisolism, Nonadrenal Disease and in Healthy Dogs

BACKGROUND Diagnosis of pheochromocytoma (PC) is based on a combination of clinical suspicion, finding an adrenal mass, increased plasma, and urine concentrations of catecholamine metabolites and is finally confirmed with histopathology. In human medicine, it is controversial whether biochemically testing plasma is superior to testing urine. OBJECTIVES To measure urinary and plasma catecholam...