[Expression of endogenous leukemia inhibitory factor in neonatal rats with periventricular leukomalacia].

ABSTRACT

OBJECTIVE: To study the changes of endogenous leukemia inhibitory factor (LIF) in neonatal rats with periventricular leukomalacia (PVL). METHODS: A PVL model of 3-day-old Wistar rats was prepared by left carotid artery ligation followed by 6% oxygen for 4 hours. The rats were sacrificed at 1, 3, 7, 14 and 28 days of hypoxia ischemia (HI), and the brain tissues were sampled. Real-Time PCR and Western blot methods were applied to analyze the expression of LIF mRNA and protein. Double staining immunofluorescence was used to detect the co-expression of LIF and GFAP. RESULTS: At 1, 3 and 7 days of HI, LIF protein level in the PVL group was higher than in the control group (P<0.01). In the PVL group, the LIF protein level on the third day after HI reached a peak and was higher than the other time points (P<0.01). The change of LIF mRNA expression showed the same tendency with LIF protein. The double staining immunofluorescence showed a co-expression of LIF and GFAP. CONCLUSIONS: LIF mRNA and LIF protein expression in astrocytes show a trend of initial increase followed by steady decline in neonatal rats with PVL, suggesting that endogenous LIF may participate in the repair of PVL.