Luobusang group and Di'ao Xinxuekang group at 0min and 1min after stepping (p<0.05-0.01).
Compared with placebo, there were significant increases in rest SaO2 in both Luobusang group
and Di'ao Xinxuekang group. SaO2 during the recovery phase of Di'ao Xinxuekang group was
significantly higher than the placebo group at 0min (p<0.01),1min (p<0.05). Conclusion: Two
drugs have effective roles in preventing the decrease in SaO2 of young men exposed to high
altitude. Di'ao Xinxuekang has an obvious effect on change of SaO2 after step-test.
279.
THE ANALYSIS OF HEART RATE VARIABILITY IN NATIVE HEALTHY TIBETAN
ADULTS AT ALTITUDE OF 3800M. Yu Yi
1
. Dept. of Cardiology, The Affiliate Hospital of
QingHai Medical college, xining Qinghai, P.R.Ch
1
.
When the function of autonomic nerve is chaotic, it seriously affects the occurrence of
cardiovascular disease, development and recovery. The analysis of Heart Rate Variability (HRV)
is a way to quantitatively measure the activity of autonomic nerve, and modulating function and
is acknowledged. Though much research has been done on the HRV of domestic and overseas
healthy subjects, there is a dearth of research on HRV of healthy native Tibetan adults at an
altitude of 3800m. Objective: The results of HRV were analyzed and compared between native
healthy Tibetan adults at altitude of 3800m and healthy Han and Tibetan adults in Xining (2260m
altitude). Methods: 100 native healthy Tibetan adults at altitude of 3800m, which included 49
men and 51 women, were studied. Their ages ranged from 22 to 77 years old; the average age was
48.35±14.68. 75 healthy Tibetans from 21 to 74 years old in Xining were selected, which include
36 men and 39 women. Their average age was 46.17±13.46. The range of time residing in Xining
was 10-45 years; the average resident time is 22.12±10.23 years. 100 healthy Han adults in
Xining from 18 to 74 years old were selected, which include 51 men and 49 women. Their
average age is 50.41±13.41years. The resident time in Xining is 18-54 years; The average
resident time was 38.45±11.22 years. HRV was measured using Holter monitoring
electrocardiogram. HRV changes in variability (SDNN, SDANN, SDNNIdex, RMSSD,
PNN50%) and frequency threshold (TP, ULF, LF, HF) were recorded. Result: The native
Tibetans at altitude of 3800m variability changes RMSSD and PNN50%(they show activity of
vagus nerve) are higher than the Tibetan and Han people in Xining. Conclusion: The activity of
the vagus nerve in native Tibetan healthy adults at altitude of 3800m is higher than the activity in
people at lower elevation.
280.
HIGH ALTITUDE AND AGING. Chu Yi-De
1
. Department of Geriatrics, Qinghai Provincial
Hospital, Xining, Qinghai., P.R.China
1
.
The objective of the paper is to study the relationship between human aging and altitude. We
examined the cardiovascular, respiratory, neurological, immune and endocrine systems of the
subjects at different altitudes. The results showed that memory declined with altitude, especially
short-term memory. Memory problems began from 40 years old and became worse after 60 years
old. The age of memory loss at high altitude began ten years earlier than that of the subjects in
lowland areas. Cardiac function and sinus node were influenced by the altitude. Lung structure
differed at high altitude compared to subjects in lowland areas. The lung function of middle and
old aged subjects living at altitude and then moving to lowland areas for 4-7 years were still
lower than those of resident subjects in lowland areas. In addition, their immune and endocrine
functions were affected as well. In conclusion, their changes indicated that environmental stresses
such as chronic hypoxia, ultraviolet (UV) light exposure and cold exposure would result in more
rapid aging at high altitude. Their mechanisms may be associated with blood flow disorders,
microcirculation dysfunctions, oxidative stress, immune abnormalities and the changes in
endocrine function.
