Blood pressure regulation in humans: calculation of an "error signal" in control of sympathetic nerve activity.

• Within an individual, diastolic blood pressure (DBP) is negatively related to sympathetic burst incidence, such that lower pressure is associated with high burst incidence. Our goal was to explore the use of a calculation of a DBP "error signal" in the control of muscle sympathetic nerve activity in men and women. Baseline muscle sympathetic nerve activity was measured in healthy young men (n=22) and women (n=28). Women had significantly lower muscle sympathetic nerve activity than men (29+/-3 versus 43+/-2 bursts per 100 heartbeats; P<0.05). For each individual, the DBP at which there is a 50% likelihood of a muscle sympathetic nerve activity burst, the "T50" value, was calculated. Mean DBP was subtracted from the T50 blood pressure as an approximate error signal for burst activation. Error signal was negative in both sexes, indicating that DBP in both sexes was higher than the DBP value associated with a 50% burst likelihood. However, average error signal was significantly larger in women (-4+/-2 mm Hg) than in men (-1+/-0 mm Hg; P<0.05 versus women). We conclude that women operate at a mean DBP greater than their T50 compared with men, and this may be a contributing factor to low basal muscle sympathetic nerve activity in women. The relationship between error signal and burst incidence may provide important insight into the control of muscle sympathetic nerve activity across sexes and in various populations.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Fysiologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Physiology (hsv//eng)

Nyckelord

Adult

Blood Flow Velocity

Blood Pressure

physiology

Blood Pressure Determination

Cardiac Output

physiology

Cohort Studies

Female

Hemodynamics

physiology

Humans

Male

Muscle

Skeletal

innervation

physiology

Muscle

Smooth

Vascular

innervation

physiology

Reference Values

Retrospective Studies

Sex Factors

Sympathetic Nervous System

physiology

Vascular Resistance

physiology

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)