EPRI to estimate the in vivo intracerebral reducing ability in adolescent rats subjected to neonatal isolation.
OBJECTIVE
To estimate the in vivo intracerebral reducing ability after acute stress in adolescent rats subjected to early neonatal isolation (NI), by performing temporal electron paramagnetic resonance imaging (EPRI) of the brain.


METHODS
An EPRI system operating at an EPR frequency of 700 MHz was used. The intracerebral reducing ability was estimated based on the halflife of the EPR signal of the blood-brain barrier (BBB)-permeable nitroxide radical. The NI treatment was performed for a period of one hour per day over postnatal days 2-9. Six-week-old rats were exposed to acute stress (immobilization for 90 minutes) prior to the EPRI study.


RESULTS
Depletion of the intracerebral reducing ability caused by the acute stress was observed; however, this depletion phenomenon did not occur in animals that were not subjected to NI.


CONCLUSIONS
The results obtained in this study prove that NI induces cerebral vulnerability to acute stress in adolescence.
National Institute of Advanced Industrial Science and Technology, Nagoya, Japan. yokohide@ni.aist.go.jp
Hidekatsu
H
Yokoyama
Shigeru
S
Morinobu
Yuto
Y
Ueda
D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism; D001812:Blood-Brain Barrier / Q000378:metabolism; D001921:Brain / Q000378:metabolism* / Q000503:physiopathology; D001928:Brain Diseases, Metabolic / Q000209:etiology* / Q000378:metabolism / Q000523:psychology; D003497:Cyclic N-Oxides / Q000378:metabolism / Q000493:pharmacokinetics; D004195:Disease Models, Animal; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D010084:Oxidation-Reduction; D011759:Pyrrolidines; D051381:Rats; D017207:Rats, Sprague-Dawley; D012149:Restraint, Physical; D012934:Social Isolation; D013315:Stress, Psychological / Q000150:complications* / Q000378:metabolism; D013997:Time Factors
D003497:Cyclic N-Oxides; D011759:Pyrrolidines; C050260:3-hydroxymethyl-2,2,5,5-tetramethylpyrroline-N-oxyl