Influence of retinoic acid on expression of insulin-like growth factors in hyperoxia-exposed premature rats
- VernacularTitle:维甲酸对高氧暴露早产大鼠胰岛素样生长因子系统表达的影响
- Author:
Hanchu LIU
;
Liwen CHANG
;
Qianshen ZHANG
- Publication Type:Journal Article
- Keywords:
Tretinoin;
Insulin-like growth factor Ⅱ;
Insulin-like growth factor-binding protein 2;
Hyperoxia;
Lung
- From:
Chinese Journal of Perinatal Medicine
2000;0(04):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the influence of retinoic acid (RA) on the expressions of insulin-like growth factor (IGF)-Ⅱ,type 2 IGF receptor (IGF-2R) and IGF binding protein (IGFBP)-2 mRNA and polypeptides in lungs of hyperoxia-exposed premature rats and its possible molecular mechanism. Methods On the 2nd postnatal day, 260 Sprague-Dawley(SD)preterm rats were randomly divided into 4 groups. Group Ⅰ: air + normal saline (NS) group; Group Ⅱ: hyperoxia(85% O_2) + NS group; Group Ⅲ: air+ RA group; Group Ⅳ: hyperoxia(85% O_2) + RA group. RA was injected to group Ⅲ, Ⅳ intraperitoneally (500 ?g/kg) since the 3rd day after birth, while NS was given to group Ⅰ,Ⅱ daily at the same time as group Ⅲ and Ⅳ. On day 4, 7, 10, 14 and 21 after birth, 8 rats in each group were killed. The mortality of preterm rats was recorded and lung radical alveolar counts (RAC) were examined. The mRNA analysis (RT-PCR) and polypeptides analysis (Western Blot) of IGF-Ⅱ, IGF-2R and IGFBP-2 were performed. Results 1. On the 4~7th day of exposure, the survival rate in all groups were similar. After 7 days of 85% O_2 exposure, the survival rate in group Ⅱ, Ⅳ dropped sharply and there was a significant difference comparing to group Ⅰ, Ⅲ( P