Plasma Volume Expansion in Rats: Effects on Thermoregulation and Exercise
Abstract
Administration of polyethylene glycol (PEG, intraperitioneal, 3 ml, 30% solution) to adult male rats (300 g) resulted in an approx. 20% increment in plasma volume (PV) 24 H after PEG injection. When these animals were exercised (9.14) m/min, level treadmill) in a warm (30 C, 30-40% relative humidity) environment, their mean endurance was increased from 67.9 (saline-treated controls CONT) to 93.6 min (P< 0.01). Total water loss was increased from 12.2 (CONT) to 17.2 g (PEG, P < 0.01). Atropine administration (ATR, 200 micrograms / kg, tail vein) significantly (P<0.05) reduced both the endurance and the salivary water loss of CONT and PEG-treated rats, where as it increased the heating rate (P< 0.01) of both groups. PEG treatment reduced (P<0.01) the hematocrit and circulating protein levels both before and subsequent to exercise in the warm environment. Clinical chemical indexes of heat/exercise injury were generally unaffected by pharmacological intervention, whereas clinical chemical response to exercise were related to the endurance time each group. We concluded that expansion of PV by PEG provided significant beneficial in warm environment. Keywords: Reprints.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1989
- Accession Number
- ADA210155
Entities
People
- C. Matthew
- M. Bosselaers
- R. P. Francesconi
- R. W. Hubbard
Organizations
- United States Army Research Institute of Environmental Medicine