ABSTRACT
<p><b>OBJECTIVE</b>To study the changes of ephrin-B3 mRNA expression and cellular apoptosis in the brain of neonatal rats with periventricular leukomalacia (PVL) and to explore the possible role of ephrin-B3 in the pathogenesis of PVL.</p><p><b>METHODS</b>Two-day-old SD rats were randomly assigned to two groups: PVL and control. PVL model was prepared by right common carotid artery ligation followed by 4-hr 6% oxygen exposure. The control group, without ligation of the artery and hypoxia treatment, was sham operated. The rats were then sacrificed and brain tissues were collected at 0, 8, 24, 48 and 72 hrs and at 7 days of hypoxic-ischemia (HI). Hematoxylin and eosin staining was used for pathologic studies. Real time RT-PCR was applied to detect brain ephrin-B3 mRNA expression. DAPI staining was applied to detect neuronal apoptosis.</p><p><b>RESULTS</b>The brain ephrin-B3 mRNA expression increased significantly in the PVL group at 8, 24, 48 and 72 hrs and at 7 days of HI compared with that of the control group (P < 0.05). The apoptotic cells in the brain of the PVL group were significantly more than that of the control group at 8, 24, 48 and 72 hrs of HI (P < 0.05).</p><p><b>CONCLUSIONS</b>ephrin-B3 mRNA expression and cellular apoptosis in the brain increased significantly in neonatal rats with PVL, which suggests that ephrin-B3 may participate in the pathogenesis of PVL in neonatal rats.</p>