when mean pulmonary arterial pressure (mPAP) was 25 mm Hg. Normals had mPAP <20 mm
Hg. Beta2-adrenoreceptor (BAR2) activity was evaluated in lymphocytes by basal and
isoproterenol-stimulated adenylate cyclase (AC) activity assay. I/D, G2215A and G2350A
polymorphisms of ACE gene, Arg16Gly and Gln27Glu polymorphisms of BAR2 were
determined by PCR. RESULTS: HAPH is associated with BAR2 desensitization (DcAMP
1.4±0.3 vs 5.8±2.3 fmol/106cells). We found that HAPH is associated with higher frequency of
Gln27Gln genotype (0.61 vs 0.45, p=0.042). Arg16Gly polymorphism did not demonstrate any
disequilibrium. HAPH was associated with I/I genotype of ACE gene (0.51 vs 0.25, p=0.01). In
Kyrgyzs I/D polymorphism was absolutely correlated with G2215A and G2350A polymorphism
of ACE gene. HAPH patients have a higher frequency of G2215G and A2350A genotypes (0.51
vs 0.25, p=0.01). CONCLUSION: HAPH in Kyrgyz highlanders is associated with higher
frequency of I/I, G2215G, A2350A genotype of ACE gene and Gln27Gln genotype of BAR2
gene.
5.
DELAYED REACTION OF HUMAN ORGANISM ON ORTHOTEST AFTER SHORT-TERM
RISE FROM 200M TO 3800M ALTITUDE. Evtushenko Alexey
1
, Ilyin Vladimir
1
, Portnichenko
Vladimir
1
. Elbrus Medical and Biological Station, NAS Ukraine
1
.
The orthostatic test allows prediction of "refusal" in certain conditions, bound with intensive
reallocation of blood in vascular channels due to changes of gravity-force load. The purpose of
this study is to determine the presence and nature of shifts in regulation of blood supply in the
delayed period after short-term stay at altitude with the help of orthotest. The research was
conducted in Northern Caucasus at 2100m, one day prior to passive ascent to 3800m altitude for
6 hours, and one day after descent. The outcomes were determined on 18-56 year-old men and
women adapted to altitude conditions. During active orthostatic test we recorded heart rate,
transthoracic tetrapolar impedance plethysmogram and arterial blood oxygen saturation. Central
hemodynamics were calculated. RESULTS: One day after descent the reaction of heart rate
during the orthotest was reduced. There was a minor augmentation of stoke volume, arterial
pressure and oxygenation of arterial blood during all periods of the test. There was also
augmentation of basal impedance of the thorax in the early stages of the orthotest, which
suggests weakening of blood outflow from vascular system of lungs. CONCLUSION: A day after
short-term stay at altitude, healthy people showed a disturbance of regulation of hemodynamics
during an orthotest, to a greater degree on the side of venous return regulation, and also
regulation of cardiac activity.
6.
ACUTE MOUNTAIN SICKNESS IS PRECEDED BY EARLY IMPAIRMENT OF
CEREBRAL AUTOREGULATION. Harald Ausserer
1
, Pritam Neupane
2
, Robb Waanders
3
,
Reinhard Ascher
4
, Ortwin Bitzer
5
, Thomas Pfefferkorn
1
, Berend Feddersen
1
. Department of
Neurology, Klinikum Grosshadern, University of Munich, Germany
1
, Human Development and
Community Services, Kathamdu, Nepal
2
, Department of Neuropsychiatry, Landeskrankenhaus
Rankweil, Austria
3
, Kundl, Austria
4
, Landau, Germany
5
.
Background: Cerebral autoregulation (CA) is known to be impaired in mountaineers and
Sherpas with and without symptoms of acute mountain sickness (AMS) at high altitude. In the
present study during a 3-week Himalayan expedition to the Khumbu Himal in Nepal we
determined whether early loss of CA may be related to later development of AMS. Methods: 33
mountaineers after baseline examinations (100 m) underwent daily examinations of middle
cerebral artery blood flow velocity (V-MCA) by transcranial Doppler sonography. The maximal
altitude reached was 6200m. Other parameters tested daily included AMS score (Lake Louise
Score), systemic arterial blood pressure (MABP), blood oxygen saturation measured by
pulsoxymetry and blood CO2 estimated by end-expiratory capnography. Results: At sea level V-
MCA was not correlated to MABP, indicating intact CA. Interestingly, after ascent to 3440 m the
relative increase of V-MCA correlated to the relative increase of MABP in the 20 volunteers that
later developed symptoms of AMS (Lake-Louise-score 3; r=0.526, p<0.021) but not in the
