Women at Altitude: Effects of Menstrual Cycle Phase and Alpha-Adrenergic Blockade on High Altitude Acclimatization.
Abstract
Background. Prior to this 3-year effort, little was known concerning the effects of high altitude exposure in women. In year 1, we evaluated the effects of menstrual cycle phase on high altitude acclimatization. Results indicated that the effects of the menstrual cycle were modest. In year 2, we evaluated the safety and efficacy of administering an a-adrenergic blocker and made selected observations during a brief exposure to an altitude of 4300 m. he drug proved to be both safe and effective. The purpose of the studies conducted in year 3 (the present annual report) was to determine the role of a-i adrenergic activity and its interaction with menstrual cycle phase across 12 days of altitude acclimatization. Sixteen young women were studied at sea level and on Pikes Peak, Colorado at 4300 m altitude. results and significance: Definite a-adrenergic blockade was achieved as shown by a rightward shift in the blood pressure response to an a-adrenergic agonist. Preliminary results are presented for basal metabolic rate, ventilation, cardiac output both at rest and during exercise, venous tone and forearm blood flow, static muscle contraction, various measures of sympathetic activation and assessment of acute mountain sickness. Various effects of both altitude and a-adrenergic blockade were observed. Analyses are continuing on other variables. Menstrual cycle correlations await hormone analysis.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1998
- Accession Number
- ADA356154
Entities
People
- Lorna G. Moore
Organizations
- University of Colorado Boulder