in tg mice decreased from 0.89 to 0.62. In tg mice plasma volume was not elevated whereas blood
volume was 25% of the body weight compared to 8% in wildtype (wt) siblings. While plasma
viscosity did not differ between tg and wt, tg whole-blood viscosity increased to a lower degree
(4-fold) than expected from corresponding hemoconcentrated wt blood (8-fold). This moderate
increase in viscosity is explicable by the up to 3-fold higher elongation of tg erythrocytes. Thus,
apart from the nitric oxide mediated vasodilatation we reported earlier, adaptation to high
hematocrit in tg mice involves regulated elevation of blood viscosity by increasing erythrocyte
flexibility. Moreover, we observed that elevated Epo serum levels protected tg6 mice from
experimentally induced myocardial infarction. Finally, overexpression of Epo in the retina
protected tg6 mice from light-induced but not from inherited retinal degeneration.
54.
PROGRESS IN STUDYING WEIGHT LOSS AT HIGH ALTITUDE AND ITS POTENTIAL
APPLICATION IN PATIENTS WITH OBESITY. Rili Ge
1
, Xiujuan Wang
1
, Huihuang Yang
1
,
Yineng Liu
1
. Research Center for High Altitude Medicine, Qinghai Xining
1
.
Obesity is becoming one of the major diseases in developed countries. It is well known that
exposure to high altitude can cause weight loss, which might be used as an alternative way to
treat patients with obesity. The objective of this study was to explore the relationship of body
weight loss induced by exposure to high altitude (4600 M) and the original altitude that the
subjects ascended from, and its potential application in treating patients with obesity. Methods:
115 construction workers who worked in the construction field of Golmud-Lhasa Railway were
enrolled in the study. Half of them are residents from sea level and the other half from eastern
Qinghai province with an average altitude of 2000 meter. Their body weight and Body Mass
Index (BMI) were measured before they ascended to the construction field at 4600 M and
measured again after one month in the field. Results: Average body weight loss for subjects from
sea level was 10.2%, with the highest one of 29%, and 2.3% for those from 2000 m. Percentage
of body weight loss in sea level subjects was positively related to their BMI (r=0.678) (P < 0.001)
but was not related to BMI in subjects from 2000 m (r=0.092). BMI in middle altitude residents is
lower than that in sea level residents. Conclusion: For people going to high altitude from sea
level, the percentage of body weight loss at high altitude is positively related with their BMI. The
results also suggest that it might be beneficial to people's well being to establish some fitness or
exercise centers at high altitude to accommodate those people with obesity.
55.
EFFECT OF HYPOXIA ON CELL ANTIOXIDANT DEFENSE SYSTEM IN RATS WITH
DIFFERENT LEVELS OF OXYGEN CONSUMPTION. Olga Gonchar
1
, Katerina Rozova
1
,
Volodymyr Portnichenko
1
. A.A.Bogomoletz Institute of Physiology NAS of Ukraine
1
.
One of the main pathogenetic aspects of Hypoxia is an excessive generation of reactive
oxygen species. The level of cell destructive damage under this condition depends on the state of
enzyme and nonenzyme antioxidant defense systems that normally regulate the level of active
oxygen metabolites. The aim of our study was to investigate the peculiarities of lipid peroxidation
(LPO), activity of antioxidant enzymes (AOE) [superoxide dismutase (SOD), catalase (CAT)]
and morphofunctional state of lung and heart tissues in rats with different reactions to hypoxia.
The animals were divided into two groups: 1- rats with low consumption of O2 (LC); 2-rats with
high consumption of O2 (HC). It was shown that in normoxia the extent of LPO as well as
activity of AOE in LC rat tissues was higher compared to HC rats. Acute hypoxia (7% O2, 30
min) caused significant changes in the biological barriers (edema, destruction) and in
mitochondria (christae dyscomplexation, edema, destruction), more pronounced in HC rats. We
found increased LPO in rat tissues in both experimental groups, but the level LPO was lower in
LC rats. Intensification of LPO in HC rats was accompanied by a significant decrease of SOD
and CAT activity in lung and myocardium. Under acute hypoxic hypoxia we found that the
activity of AOE in LC rats was insignificantly increased or unchanged compared to control.
