Total plasma dopamine/norepinephrine ratio in catecholamine-secreting himors: Its relation to hypertension
Blood pressure; Dopamine; Norepinephrine; Sulfoconjugated catecholamines
We used a radioenzymatic method to determine plasma levels of free and total (free plus sulfoconjugated) norepinephrine and dopamine in 20 children with neuroblastoma (two were hypertensive), seven patients with pheochromocytoma, and 39 normotensive controls (24 children and 15 adults). No significant differences were noted between the two control groups. Patients with neuroblastoma and pheochromocytoma showed significantly higher levels of free and total norepinephrine than controls (p < 0.01), and those with pheochromocytoma had higher levels than those with neuroblastoma (p < 0.01). Although the differences were not statistically significant, free dopamine was higher in both groups of patients than in controls. Total dopamine was significantly higher in patients than in controls (p < 0.01). A positive correlation was noted between levels of total norepinephrine and total dopamine in controls (r=0.41, p < 0.05) and in patients with neuroblastoma (r=0.72, p < 0.001). Such a correlation was not found in patients with pheochromocytoma. The total dopamine/total norepinephrine ratio was higher (p < 0.005) in patients with neuroblastoma than in controls and patients with pheochromocytoma. Patients with pheochromocytoma had significantly lower ratios than the other groups (p < 0.001). A negative correlation was found between the ratios in the different groups and either systolic (p < 0.001) or diastolic (p < 0.001) blood pressure. Our results not only support a role for plasma dopamine hi the regulation of blood pressure but also suggest that, regardless of the actual levels of both catecholamines, a balance has to be achieved hi order to maintain normal blood pressure levels. © 1988 American Heart Association, Inc.
Puyo, A., Levin, G., Armando, I., & Barontini, M. (1988). Total plasma dopamine/norepinephrine ratio in catecholamine-secreting himors: Its relation to hypertension. Hypertension, 11 (2). Retrieved from https://hsrc.himmelfarb.gwu.edu/smhs_medicine_facpubs/3771