Accession Number : ADA192656

Title :   Plasma Volume Expansion in Rats: Effects on Thermoregulation and Exercise,

Corporate Author : ARMY RESEARCH INST OF ENVIRONMENTAL MEDICINE NATICK MA

Personal Author(s) : Francesconi, R P ; Bosselaers, M ; Matthew, C ; Hubbard, R

PDF Url : ADA192656

Report Date : Feb 1988

Pagination or Media Count : 25

Abstract : Administration of polyethlene glycol (PEG, intraperitoneal, 3ml, 30% solution) to adult, male rats (300g) resulted in an approximate 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% rh) environment, their mean endurance was increased from 67.9 min (saline-treated controls, CONT) to 93.6 min. Total water loss was increased from 12.2g (CONT) to 17.2 g (PEG). Atropine administration (ATR, 200 ug/kg, tail vein) significantly reduced both the endurance and the salivary water loss of CONT and PEG-treated rats while increasing the heating rate of both groups. PEG treatment reduced the hematocrit and circulating protein levels both prior and subsequent to exercise in the warm environment. Clinical chemical indices of heat/exercise injury were generally unaffected by pharmacological intervention while clinical chemical responses to exercise were related to the endurance time of each group. We concluded that expansion of PV by PEG provided significant beneficial effects on performance and thermoregulation during exercise in a warm environment. Keywords: Polyethylene glycol, Atropine, Salivation, Physical performance, Indices of heat injury.

Descriptors :   *BLOOD PLASMA, *BLOOD VOLUME, *EXERCISE(PHYSIOLOGY), *DRUGS, *HEAT TOLERANCE, *ENDURANCE(PHYSIOLOGY), ATROPINE, CIRCULATION, CLINICAL MEDICINE, EXPANSION, GLYCOLS, HEAT, HEATING, HEMATOCRIT, INDEXES, INTERVENTION, LOSSES, MALES, MEAN, PERFORMANCE(HUMAN), PHARMACOLOGY, POLYETHYLENE, PROTEINS, RATES, RATS, RESPONSE(BIOLOGY), SALIVA, TEMPERATURE CONTROL, TIME, VEINS, WATER, WOUNDS AND INJURIES, HEAT STRESS(PHYSIOLOGY)

Subject Categories : Stress Physiology
      Pharmacology

Distribution Statement : APPROVED FOR PUBLIC RELEASE