[Changes in the rheological indicators of the blood and hemodynamics during 14-day anti-orthostatic hypokinesia].
Nine essentially healthy subjects, aged 25 to 42 years, were exposed to head-down bed rest (-8 degrees). On bed rest days 3, 7 and 14 the following rheological and hemodynamic parameters were measured: blood dynamic viscosity, Caisson viscosity, yield limit, red blood cell aggregation, stroke volume, cardiac output, and total peripheral resistance. Rheological parameters were measured by means of a rotation viscosimeter at 25 degrees C +/- 0.1. Hemodynamic parameters were measured by the method of integrated rheography. Blood was withdrawn from the cubital vein. The results give evidence that dynamic and Caisson viscosity increased significantly, reaching a peak by bed rest day 14. The sequence of hemodynamic changes followed the same pattern as rheological changes. Analysis of the results shows that there is a good correlation between the above parameters, especially by bed rest day 14. Thus, it can be concluded that there is a vascular mechanism involved in the compensatory restructuring of the vascular system at the tissue level in response to blood redistribution and fluid loss during bed rest.
Ivanov
A P
AP
Goncharov
I B
IB
Repenkova
L G
LG
D000328:Adult; D001809:Blood Viscosity / Q000502:physiology*; D004903:Erythrocyte Aggregation / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D007103:Immobilization / Q000502:physiology*; D008297:Male; D008954:Models, Biological; D008955:Models, Cardiovascular; D011187:Posture; D013997:Time Factors
Izmeneniia reologicheskikh pokazateleĭ krovi i gemodinamiki v usloviiakh 14-sutochnoĭ antiortostaticheskoĭ gipokinezii.