[Effect of antiorthostatic pre-training on transcapillary turnover of fluids in extra- and intracranial vessels of rats in antiorthostatic hypokinesia].

Dynamics of the transcapillary turnover of liquids in the brain and soft tissues of the head was studied in pre-trained small laboratory animals (rats) during antiorthostasis, and their controls. Training for antiorthostasis consisted of tail-suspension for 2 hours in the period of two weeks. The transcapillary turnover of liquids was determined based on the arteriovenous difference in blood density (AVBD). Blood density was measured with the equipment of Anton Paar K.G. (Austria). Rats in the horizontal position did not exhibit any apparent trend in the dynamics of blood transcapillary turnover. Blood drain from the interstitial space at the time of return of the antiorthostatic rats into the horizontal position was dependent on the length of antiorthostatis. Beginning from the fifth hour of tail suspension, changed AVBD sign was an indication of edema of the muzzle soft tissue. This phenomenon was not observed in the pre-trained rats. Similar results were obtained in the investigation of cerebral vessels AVBD. Hence, changes in the transcapillary turnover of liquids in cranium during antiorthostatic hypokinesia point to the dominance of liquid filtration into the extravascular space. Antiorthostatic pre-training precludes liquid deposition in the interstitial space of the brain and the cerebral soft tissue.