P60 to P68 mice after 2km-IH. The improvement of the IH-induced MWM task was attenuated in
P85 mice, but the facilitative trend seemed to be concerned in 2 km IH-treated mice. These results
suggest that the acquisition and retention of spatial tasks may be improved in postnatal
developmental mice treated with intermittent hypoxia of 2km altitude. The mechanism of
improved spatial task performance may be due to facilitated synaptic plasticity and triggered
CREB phosphorylation in this model of mice. * This work is supported by the grant from NSFC
(Major Project No. 30393134 and Project No. 30070289; 30270232).
297.
OXYGEN SATURATION PULSE RATE AND ACUTE MOUNTAIN SICKNESS IN
NEWCOMERS AT HIGH ALTITUDE. Shenglin Zhang
1
. Dept. Internal Medicine, Xining
Railway Hospital, Xining, Qinghai, PRC
1
.
To assess the relation between oxygen desaturation and acute mountain sickness (AMS), 56
healthy male Han newcomers were studied, their mean age was 40.5 yr with a range of 20-52 yr,
all were sea-level residents and first entry to high mountain to inspect the construction of the
Qinghai-Tibet Railroad by bus for 48 hr from Golmud (2801 m) to Lhasa (3658 m) through Toe
Toe River (4660 m) and Tanggula Pass (5231 m), each station stay for 2-3 hr and examined
before and after inspection. Oxygen saturation (SaO2) and pulse rate (PR) were examined
simultaneously using a finger oximeter (Detex-Ohmeda, USA ). AMS scoring system was used
the Lake Louise Consensus (1991). At 2801 m, all subjects were entirely free of AMS with a near
normal SaO2 ( mean 93.3±9.0, SD) and PR (mean 74.3±6.8 bpm,SD), and this was as the
baseline for control. At 4660 m, the SaO2 decreased significantly(mean 84.6±14.1, P <0.01) and
PR increased markedly (mean 90.5±7.1, P <0.01), 12 subjects (21.4%) were defined as suffering
from AMS. The most severe desaturation was observed at 5231 m (mean SaO2 was 78.7±10.8,
P<0.001) with further increased PR (mean 108.3±7.0, P <0.001). 16 subjects defined as moderate
or severe AMS and need to supplementary oxygen. When entry to Lhasa (3658 m), SaO2 remain
lower (mean 90.2±7.3, P <0.05) and PR remain higher (mean 83.0±5.8. P<0.05) than those of the
Golmud, 26 subjects (46.4%) remain had one or two symptoms, but they were return to Beijing
next day. Thus we concluded that SaO2 lower than 85% and PR higher than 90 bpm at rest
usually indicated that AMS is more likely to occur.
298.
SOD, GSH, CAT, GSH-PX AND NA+K+ ATP-ASE OF BRAIN IN RATS DURING ACUTE
DECOMPRESSION HYPOXIA. Yan-Meng Zhang
1
, Xi-Wei Tang
1
, Zhong-Yuan Shi
1
.
Department
1
.
In this study we examined the effect of Gingseng and Gingko on SOD, GSH, CAT, GSH-PX
and Na+,K+ ATP-ase of brain in rats during acute decompression hypoxia. Adult SD rats were
randomly divided into normoxic control (NC), acute decompression hypoxia (AH), Gingseng and
Gingko mixture + acute decompression hypoxia (MH) groups. For the later groups rats were
exposed to simulated 8000m high altitude in a hypobaric camber for 7h. The concentration of
GSH and CAT, activity of SOD, GSH-PX and Na+,K+ ATP-ase in cerebral tissue measured.
Gingseng and Gingko mixture was administrated orally for 7 days in MH group before
decompression hypoxia. The other two groups were treated with the same volume water. The
results of our experiments show that the concentration of GSH and CAT in cerebral tissue was
significantly decreased in AH group, but it was significantly increased in MH group. The activity
of SOD, GSH_PX and Na+,K+ATP-ase in cerebral tissue in AH group was significantly reduced,
while Gingseng and Gingko mixture decreased this reduction. Therefore, the Gingseng and
Gingko mixture has significant role of protective effect on brain function during acute
decompression hypoxia. The mechanism of the effect of Gingseng and Gingko mixture was
inhibit lipid peroxidation of brain cells.
