Faculty Collaboration Database

Hormonal responses and blood pressure maintenance in normal and hypertensive subjects during acute blood loss. Hypertension 1987 May;9(5):423-8

Date

05/01/1987

Pubmed ID

3552977

DOI

10.1161/01.hyp.9.5.423

Scopus ID

2-s2.0-0023220945 (requires institutional sign-in at Scopus site)   8 Citations

Abstract

Blood pressure (BP) and plasma indices of three major pressure control systems--plasma norepinephrine and epinephrine, plasma renin activity (PRA), and plasma arginine vasopressin--were measured simultaneously in 12 normal and 15 mildly essential hypertensive subjects before and after removal of 480 ml of blood by phlebotomy, to determine if there were differences in the compensatory response to acute blood loss. Responses to postural stress (change from supine to sitting position) following phlebotomy were also compared in a second group of subjects. Before phlebotomy, supine plasma hormone levels did not differ in the two groups. After phlebotomy, both groups exhibited only slight decreases (5 mm Hg) in systolic BP and a transient rise in heart rate. Only plasma norepinephrine increased significantly in both groups (35% above control in normal and 43% in hypertensive subjects). Similar results were obtained in a second group of normal and hypertensive subjects, who were also subjected to a 10-minute postural challenge after phlebotomy. After 10 minutes in a sitting position, BP in these subjects remained unchanged but heart rate and plasma norepinephrine increased further to levels almost twice that produced by phlebotomy alone. Plasma epinephrine levels and PRA also increased with this additional stress, but plasma vasopressin remained unchanged. Changes in BP, heart rate, plasma norepinephrine and epinephrine, and PRA did not differ significantly between the two groups. These data indicate that hypertensive subjects are as capable as normal subjects of maintaining BP when subjected to standard phlebotomy, the sympathetic nervous system appears to be the predominant pressor mechanism activated following an acute, nonhypotensive blood loss in both groups of subjects,(ABSTRACT TRUNCATED AT 250 WORDS)

Author List

Velasquez MT, Menitove JE, Skelton MM, Cowley AW Jr

Author

Allen W. Cowley Jr PhD Professor in the Physiology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adult
Arginine Vasopressin
Blood Pressure
Blood Volume
Bloodletting
Epinephrine
Female
Heart Rate
Hormones
Humans
Hypertension
Male
Middle Aged
Norepinephrine
Potassium
Renin
Sodium