Operation Everest II. Plasma Lipid and Hormonal Responses
Abstract
Lipid metabolism has been shown to be altered with exposure to high altitude. Weight loss attributable to loss of body fat or lean body mass has been reported with long-term exposure to high altitude. Furthermore, exposure to high altitude led to increased circulating triglyceride levels and reduced or unchanged plasma cholesterol concentrations. Thus, the effects of exposure to high altitude on lipid metabolism appear to be complex, interrelated processes involving multiple responses by the body. Lipid metabolism is a dynamic process involving integrated series of events. In blood, fats are transported in lipoprotein particles that consist of a core of lipid, cholesterol ester or triglyceride, stabilized by an outer layer of protein and phospholipid. Dietary fats are transported as chylomicrons and are not present in fasting plasma of healthy, normolipemic individuals. Endogenously derived plasma lipids are contained in three major lipoprotein classes: very low density lipoprotein (VLDL), a triglyceride-rich lipoprotein synthesized by the liver; and two cholesterol-rich particles, low density lipoprotein (LDL) and high density lipoprotein (HDL). VLDL has been shown to be a direct precursor of LDL and HDL, although nascent HDL can also be secreted directly by the liver.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1988
- Accession Number
- ADA198547
Entities
People
- Allen Cymerman
- Charles S. Houston
- Howard J. Green
- John R. Sutton
- Madeleine S. Rose
- Patricia M. Young
Organizations
- United States Army Research Institute of Environmental Medicine