Expression and action of vascular endothelial growth factor and its receptor in a rat model of retinopathy of prematurity.
- Author:
Xian-qiong LUO
1
;
Guo-sheng LIU
;
Ri-quan LAI
;
Chuan NIE
;
Kun-he WU
;
Ye TIAN
;
Ming-han XIA
;
Ju-ling KANG
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Animals, Newborn; Disease Models, Animal; Female; Hypoxia; Immunohistochemistry; Male; Rats; Rats, Sprague-Dawley; Receptors, Vascular Endothelial Growth Factor; analysis; Retina; chemistry; pathology; Retinal Diseases; metabolism; pathology; Vascular Endothelial Growth Factor A; analysis
- From: Chinese Journal of Pediatrics 2004;42(7):511-515
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo explore the expression of vascular endothelial growth factor (VEGF) and its receptors (flt-1 and flk-1) in the retina of retinopathy of prematurity (ROP), and its relation to the alteration of retinal blood vessels.
METHODSEighty-six newborn Sprague-Dawley rats were randomly divided into hyperoxia and air groups, then each group was further divided into 1, 3, 7 and 14 days subgroups. The rats in hyperoxia group inhaled 75% oxygen and ROP model was thus set up. These animals were sacrificed respectively after 1, 3, 7 and 14 days, then the retinal endothelial cells were marked by CD34 to observe the change of retinal blood vessels. The expression of VEGF, flt-1 and flk-1 in the retina was measured by immunohistochemistry.
RESULTSThe retinal capillary density index (RCDI) in control group increased as days went on (F = 21.589, P < 0.01, but it was the least on the 7th day in hyperoxia group, after the rats had been returned to air for 7 days, RCDI increased significantly (F = 67.885, P < 0.01); In the control group, the expression of VEGF and flk-1 was the strongest in the retina on the 7th day, the result had significant difference as compared with the 1st and 14th day (P < 0.05). The expression of VEGF and flk-1 on the 7th day in hyperoxia group was weaker than that of control group (P < 0.05). But on the 14th day in hyperoxia group, they were stronger than that of control (P < 0.05). The localization of the expression of flt-1 was changed when blood vessels altered, but there was no significant difference in expression intensity as a whole (P > 0.05).
CONCLUSIONWhen the premature retina was exposed to hyperoxia, the expression of VEGF and flk-1 was reduced, and retinal blood vessels were also decreased; but the expression of VEGF and flk-1 was stronger in retina when premature rats were exposed to relative hypoxia, and the retinal blood vessels also increased significantly. It is concluded that VEGF and flk-1 may play important roles in the development of retinal blood vessels and its change in ROP. However, flt-1 has less effect compared with flk-1.
