and 13.0% bought it abroad. Those who used acetazolamide during the mountain climbing were
63 male, and 6 female members, corresponding to 23.3%, and 16.7%, respectively. Their age-
range was from 20's to 60's in male, and 6 out of 7 were 50's in female. There was no significant
relationship between the use of acetazolamide and the presence of past mountain sickness,
although those with experience of high-altitude mountain climbing tended to use the drug. The
main purpose of the drug use was more for prevention (73%) than for treatment. Although there
appears to be no widely determined dose of medication, majority of members took the drug 250-
500mg per day, once or twice daily, for a couple to several days. Among the members who took
the drug 125-500mg per day, 30 out of 49 felt they were effective. As for side effects, 18
members (26.5%) complained numbness in finger tips, 1 member (1.4%) shivering, and 1
member (1.4%) increase in urine volume. There was no significant difference in mountains,
duration of climbing, attained altitude between the teams which used the drug and those which
carried but did not use it, 20 out of 46 teams belonging to the latter.
86.
THE IMPORTANCE OF ACUTE HYPOXIC TOLERANCE WITH ALTITUDE CHAMBER
AND BEFORE PLATEAU EXPOSED. Xiao Hua-Jun
1
, Zheng Xiao-Hui
2
, Zhou Ya-Jun
2
.
Institute of Aviation Medicine, Beijing
1
, Institute of Aviation Medicine, Beijing
2
.
It is generally recognized that the most serious hazard during the working or travel to the
altitude (plateau) is hypobaric hypoxia. In order to recognized that the relationship between acute
hypoxic tolerance with altitude chamber and hypoxic response to plateau has been investigated
Method The tolerance of acute hypoxia was carried out on the subjects who were going to
highland to carry out a task.100 people, 97 men, 3 female, age from 18y to 58y, were exposed to
5000m altitude breathing air in altitude chamber for 30min or 20 people to 7100m for 10 min
after they have their physique examined. Then the response after plateaus staying was
investigated. Results 51 people had stayed for a week in plateaus smoothly and returned to the
inland, without the harmful effect. Some of them felt tired, gasp for breath when they did physical
labor, or had a poor appetite, dizzy at first and disappeared 2-3 days later during highland. The
results we have investigated show that the people who have a good acute hypoxic tolerance have
the better tolerance adaptive ability in plateau. The hypoxic tolerance test with the altitude
chamber, which is used for evaluating pilots flying ability, is suitable for examining the hypoxic
tolerance of highland. By this way the people going to plateau to working or to go sightseeing
know what the tolerance he is, and lighten their frightens and restless to increase their safety
feeling, and how to take care to himself. Conclusion The tolerance test for altitude hypoxia is a
special test for the altitude effect on humans while the common medical examination couldn't'
take the place of. So our preliminary investigation suggests that all people going to the plateau for
work or travel should take an examination of altitude hypoxia before going.
87.
EXERCISE AT SIMULATED HIGH ALTITUDE STIMULATES NEOVASCULARIZATION
IN SKELETAL MUSCLE AND MYOCARDIUM IN RATS. Qingyuan Huang
1
, Yuqi Gao
1
,
Bingyong Sun
1
. Department of Pathophysiology and High Altitude Physiology, Third Military
Medical University, Chong
1
.
Objective: To study the effects of exercise under hypoxia on capillary formation in skeletal
muscle and myocardium. Methods: Wistar rats were divided into 3 groups: I normoxic control; II
hypoxia and III hypoxia+exercise. Rats of II and III groups were first brought to 4000m altitude,
where rats of the III group were forced to swim for 1h/day (6 days/week). Then the animals were
exposed to 5000m (23h/day). The total hypoxic exposure time was 35 days. Cross-sectional area
(CSA) of muscle fiber, capillary density (CD) and capillary/fiber ratio (C/F) were assayed by
myofibrillar ATPase and alkaline phosphatase histochemistry in skeletal muscle and
myocardium. Results: 5-week hypoxia exposure resulted in a decrease in CSA of skeletal muscle
fiber and an increase in CD, but the C/F remained unchanged. After 5-week- of exercise +
hypoxia, the muscle fibers did not atrophy. CD and C/F increased. Neovascularization occurred
