All issues > Volume 44(11); 2001

Original Article

J Korean Pediatr Soc. 2001;44(11):1278-1288. Published online November 15, 2001.

Effect of Resuscitation with High Concentration Oxygen on a Rat Model of Neonatal Hypoxic-Ischemic Brain Injury

Dong Seok DS Lee¹, Su-Hee SH Kwak¹, Heng-Mi HM Kim¹, Yoon Kyung YK Sohn²

¹Department of Pediatrics, College of Medicine, Dongguk University, Kyongju, Korea
¹Department of Pediatrics, College of Medicine, Kyungpook University, Taegu, Korea
²Department of Pathology, College of Medicine, Kyungpook University, Taegu, Korea

Correspondence Heng-Mi HM Kim ,Email: hmkim@knu.ac.kr or @knuh.knu.ac.kr

Abstract

Purpose
: This study was undertaken to determine whether any features of apoptosis would occur in the established model of cerebral hypoxia-ischemia in neonatal rats. It was also undertaken to evaluate the effect of post-insult hyperoxia on hypoxic ischemic cerebral injury.
Methods
: Seven-day-old neonatal rats underwent unilateral carotid artery dissection followed by 2 hours of hypoxia. To this end rat pups, allocated into 2 groups, were resuscitated with high concentration O2(>FiO2 95%) or room air for a 1-hour period. All of them were killed at 3 days after the above procedures. Their brains were perfusion fixed and removed to examine tissue damage by light microscope and apoptosis by terminal deoxynucleotidyl transferase mediated dUTP- biotin nick end labeling(TUNEL) reactivity.
Results
: The result demonstrates that hypoxia-ischemia model induces tissue damage and TUNEL. Post-insult exposure to high reactivity concentration O2 does not aggravate hypoxic-ischemic cerebral injury 3 days after the insult but increases TUNEL reactivity in injured tissue.
Conclusion
: These findings suggest that many cells die by apoptosis following hypoxia-ischemia in neonatal brain and resuscitation with high concentration O2 seems to provide an adverse effect over a brain injury by induction of apoptosis.

Keywords :Hypoxia, Ischemia, Newborn rat, TUNEL, Hyperoxia, Resuscitation