Plasma Norepinephrine in the Evaluation of Baroreceptor Function in Humans
The value of plasma norepinephrine measurement in assessing baroreceptor-mediated changes in sympathetic vasomotor activity was studied in seven healthy normotensive volunteers. Blood pressure was decreased by graded steady-state infusions of sodium nitroprusside (25–100 μg/min) and increased by inf...
Gespeichert in:
Veröffentlicht in: | Hypertension (Dallas, Tex. 1979) Tex. 1979), 1982-07, Vol.4 (4), p.566-571 |
---|---|
Hauptverfasser: | , , , |
Format: | Artikel |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | The value of plasma norepinephrine measurement in assessing baroreceptor-mediated changes in sympathetic vasomotor activity was studied in seven healthy normotensive volunteers. Blood pressure was decreased by graded steady-state infusions of sodium nitroprusside (25–100 μg/min) and increased by infusions of phenylephrine (25–100 μ/) at rates producing a 10° to 20° change in diastolic blood pressure. Sodium nitroprusside produced significant decreases in diastolic blood pressure (p < 0.01) and calculated mean arterial blood pressure (p < 0.005), and increases in heart rate (p < 0.001) and plasma norepinephrine (p < 0.001). Phenylephrine administration produced increases in systolic (p < 0.005), diastolic (p < 0.005), and mean blood pressure (p < 0.001). Heart rate (p < 0.001) and plasma norepinephrine (p < 0.05) fell. The absolute changes in diastolic and mean pressure and heart rate were not significantly different for the two drugs, but were of opposite sign; however, the increase in plasma norepinephrine during hypotension was greater than the decrease during hypertension (p = 0.02). We conclude that plasma norepinephrine changes appropriately in response to altered blood pressure and that the response is greater to a given fall than to a rise in blood pressure, consistent with known changes in sympathetic vasomotor outflow. (Hypertension 4:566–571, 1982) |
---|---|
ISSN: | 0194-911X 1524-4563 |
DOI: | 10.1161/01.hyp.4.4.566 |