Gender differences in autonomic cardiovascular regulation: spectral, hormonal, and hemodynamic indexes

• Published in: Journal of applied physiology (1985) Vol. 91; no. 6; pp. 2611 - 2618
• Main Authors: Evans, Joyce M, Ziegler, Michael G, Patwardhan, Abhijit R, Ott, J. Blaine, Kim, Charles S, Leonelli, Fabio M, Knapp, Charles F
• Format: Journal Article
• Language: English
• Published: Legacy CDMS Am Physiological Soc 01.12.2001; American Physiological Society
• Subjects: Adult; Autonomic Nervous System - physiology; Biological and medical sciences; Blood Pressure; Cardiovascular Physiological Phenomena; Circulatory system; Coronary vessels; Epinephrine - blood; Female; Fundamental and applied biological sciences. Psychology; Gender; Heart; Heart Rate; Hemodynamics - physiology; Humans; Life Sciences (General); Male; Norepinephrine - blood; Pancreatic Polypeptide - blood; Regional Blood Flow; Sex Characteristics; Skin - blood supply; Space life sciences; Stroke Volume; Vascular Resistance; Vertebrates: cardiovascular system; Non-Nasa Center; Nasa Discipline Cardiopulmonary; Human; Cardiovascular control; Variability; Sex; Smooth muscle; Spectral analysis; Heart rate; Autonomic nervous system; Blood vessel; Arterial pressure; Circulatory system; Hemodynamics; Muscular tonus; NASA Discipline Cardiopulmonary; Non-NASA Center
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/jappl.2001.91.6.2611

1  Center for Biomedical Engineering and Division of Cardiology, University of Kentucky, Lexington, Kentucky 40506-0070; and 2  Department of Medicine, University of California, San Diego, California 92103-8341 The autonomic nervous system drives variability in heart rate, vascular tone, cardiac ejection, and arterial pressure, but gender differences in autonomic regulation of the latter three parameters are not well documented. In addition to mean values, we used spectral analysis to calculate variability in arterial pressure, heart rate (R-R interval, RRI), stroke volume, and total peripheral resistance (TPR) and measured circulating levels of catecholamines and pancreatic polypeptide in two groups of 25   ± 1.2-yr-old, healthy men and healthy follicular-phase women (40   total subjects, 10 men and 10 women per group). Group 1  subjects were studied supine, before and after - and muscarinic autonomic blockades, administered singly and together on separate days of study. Group 2  subjects were studied supine and drug free with the additional measurement of skin perfusion. In the unblocked state, we found that circulating levels of epinephrine and total spectral power of stroke volume, TPR, and skin perfusion ranged from two to six times greater in men than in women. The difference (men > women) in spectral power of TPR was maintained after - and muscarinic blockades, suggesting that the greater oscillations of vascular resistance in men may be -adrenergically mediated. Men exhibited muscarinic buffering of mean TPR whereas women exhibited -adrenergic buffering of mean TPR as well as TPR and heart rate oscillations. Women had a greater distribution of RRI power in the breathing frequency range and a less negative slope of ln RRI power vs. ln frequency, both indicators that parasympathetic stimuli were the dominant influence on women's heart rate variability. The results of our study suggest a predominance of sympathetic vascular regulation in men compared with a dominant parasympathetic influence on heart rate regulation in women. catecholamines; spectral power; stroke volume; peripheral resistance; atropine; propranolol; autonomic balance; skin perfusion; arterial pressure; heart rate