title: [Effect of loss of consciousness induced by repeated lower body negative pressure on blood-brain barrier permeability in rats].
abstract: To investigate the effect of loss of consciousness induced by repeated +Gz on the brain and its mechanism, changes of blood-brain barrier (BBB) permeability and brain water content after repeated lower body negative pressure (LBNP) induced loss of consciousness were observed in 30 rats. Rats were anesthetized and exposed to LBNP (-4.0 kPa). The pressure rapidly returned to control level 2 min after EEG became isoelectric. The BBB permeability was measured using lanthanum trace labeling with electron microscopy and brain water content was determined after one or three LBNP exposures. Most tight junctions among endothelial cells opened through which the lanthanum entered into the neurons and extra cellular space and water content in brain tissues increased significantly (P < 0.05) 1 h after 3 LBNP exposures. It demonstrated that 3 exposures to LBNP induced loss of consciousness can result in an increase of BBB permeability in rats, which may play an important role in the development of G-induced brain edema.
authors.affiliation: Department of Aerospace Biodynamics, Fourth Military Medical University, Xi'an, China.
authors.forename: X
authors.initials: X
authors.lastname: Sun
authors.forename: X
authors.initials: X
authors.lastname: Wu
authors.forename: X
authors.initials: X
authors.lastname: Li
authors.forename: S
authors.initials: S
authors.lastname: Jiang
authors.forename: Y
authors.initials: Y
authors.lastname: Yao
authors.forename: L
authors.initials: L
authors.lastname: Zhang
mesh_terms: D000337:Aerospace Medicine; D000818:Animals; D001812:Blood-Brain Barrier / Q000502:physiology*; D001921:Brain / Q000378:metabolism* / Q000502:physiology / Q000648:ultrastructure; D002199:Capillary Permeability / Q000502:physiology; D018471:Hypergravity; D007811:Lanthanum / Q000493:pharmacokinetics; D008150:Lower Body Negative Pressure / Q000009:adverse effects*; D008854:Microscopy, Electron; D010296:Parietal Lobe / Q000378:metabolism / Q000648:ultrastructure; D051381:Rats; D017207:Rats, Sprague-Dawley; D014474:Unconsciousness / Q000209:etiology / Q000503:physiopathology*; D014867:Water / Q000378:metabolism
chemical_list: D014867:Water; D007811:Lanthanum