[Effect of repeated cerebral ischemia induced by lower body negative pressure on neuronal morphology and ions contents, ATPase activity of brain tissue in rats].
To investigate the effect of repeated + Gz-induced loss of consciousness on the brain and its mechanism, we observed the changes of ions contents, ATPase activity of brain tissues and neuronal morphology after repeated cerebral ischemia induced by lower body negative pressure(LBNP) in rats. Thirty male Sprague-Dawley rats were divided into 3 groups randomly. Rats were anesthetized and exposed to LBNP of -4 kPa at a rate of 0.67 kPa/s. The pressure rapidly returned to control level 2 min after EEG becomes isoelectric. Cortical Na(+)-K(+)-ATPase activity decreased significantly lh after one LBNP exposure (P < 0.05), While Na+, K+ and water contents of brain tissues showed a tendency to increase (P > 0.05). Na(+)-K(+)-ATPase activity decreased significantly while Na+, K+ and water contents increased significantly 1 h after three LBNP exposures, and ischemic changes were found in a few neurons. It suggested that three cerebral ischemia exposure induced by LBNP can result in disturbance of ion homeostasis and neuronal damage.
Sun
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X
Department of Aerospace Biodynamics, The Fourth Military Medical University, Xi'an, China.
Jiang
S
S
Wu
X
X
Yao
Y
Y
Zhang
L
L
D000818:Animals; D002545:Brain Ischemia / Q000201:enzymology / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D002540:Cerebral Cortex / Q000201:enzymology / Q000378:metabolism* / Q000473:pathology; D006624:Hippocampus / Q000473:pathology; D008150:Lower Body Negative Pressure / Q000009:adverse effects*; D008297:Male; D009474:Neurons / Q000473:pathology*; D011188:Potassium / Q000378:metabolism; D017966:Pyramidal Cells / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012964:Sodium / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D014867:Water / Q000378:metabolism
D014867:Water; D012964:Sodium; D000254:Sodium-Potassium-Exchanging ATPase; D011188:Potassium