Chronic hormone replacement therapy does not alter resting or maximal skin blood flow

• Published in: Journal of applied physiology (1985) 1998-08, Vol.85 (2), p.505-510
• Main Authors: Brooks-Asplund, E. M, Kenney, W. L
• Format: Article
• Language: English
• Subjects: Anatomy & physiology; Biological and medical sciences; Blood; Blood Pressure - physiology; Circulatory system; Drug therapy; Estrogen Replacement Therapy - adverse effects; Estrogens; Female; Forearm - blood supply; Hormones. Endocrine system; Humans; Laser-Doppler Flowmetry; Medical sciences; Middle Aged; Pharmacology. Drug treatments; Regional Blood Flow - drug effects; Skin - blood supply; Vascular Capacitance - physiology; Vital Capacity - physiology
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/jappl.1998.85.2.505

Noll Physiological Research Center, Pennsylvania State University, University Park, Pennsylvania 16802-6900 Postmenopausal women on estrogen replacement therapy (ERT) regulate body core temperature at a lower baseline level at rest in a thermoneutral environment. We conducted a series of studies to test whether, in a thermoneutral environment, chronic ( 2 yr) oral ERT significantly alters baseline skin blood flow (SkBF) and cutaneous vascular conductance (CVC) and whether ERT alters maximal CVC (CVC max ) and SkBF in postmenopausal women. In the first set of studies, forearm blood flow (FBF) was measured by venous-occlusion plethysmography in 24 postmenopausal women: 8 not taking exogenous hormone therapy (No HRT group), 8 on ERT, and 8 receiving combination of estrogen and progesterone therapy, at rest and during prolonged (1 h) local heating of the forearm at 42°C. Mean arterial pressure (MAP) was measured by brachial auscultation before each set of FBF measurements to calculate forearm vascular conductance (FVC = FBF/MAP). SkBF was measured by laser-Doppler flowmetry (LDF), and CVC was calculated as LDF/MAP and standardized as %CVC max . Baseline FVC, %CVC max , and maximal FVC were not significantly different among the three groups of women. In the second set of experiments, LDF in ERT and No HRT groups was measured at rest in both thermoneutral and warm environments. %CVC max was again not significantly different between ERT and No HRT groups at thermoneutral ambient temperatures and increased similarly in the warm environment. Therefore, chronic exogenous ERT does not appear to influence either baseline or maximal SkBF. vascular conductance; estrogen; progesterone; cutaneous blood flow; vasodilation; postmenopausal women