Powers M R, Planck S R
Department of Pediatrics, Oregon Health Sciences University, Portland 97201, USA.
Curr Eye Res. 1997 Mar;16(3):177-82. doi: 10.1076/ceyr.16.3.177.15406.
Transforming growth factor-alpha (TGF-alpha) is a mitogenic polypeptide for a variety of different cells types including retinal neurons and glial cells. We have examined the temporal and spatial expression of TGF-alpha and its receptor in the normal and hyperoxia-exposed neonatal rat retina to determine if the expression is consistent with a role in retinal development and response to retinal injury.
We have used immunohistochemistry to examine TGF-alpha and epidermal growth factor receptor (EGF-R) on postnatal days (1, 5, 10, 14, 18, and 25). To examine TGF-alpha and EGF-R expression after retinal injury we studied the retinas from rats which were exposed to 80% oxygen for 10 days and then recovered in room air. Immunolocalization of type IV collagen was performed to examine the retinal vasculature development after hyperoxia.
The pattern of TGF-alpha and EGF-R expression in the neural retina evolved from a diffuse pattern on postnatal day 1 to restricted sites on postnatal day 14. The TGF-alpha immunoreactivity was consistent with localization in Müller cells on postnatal day 14. Both TGF-alpha and EGF-R patterns were altered in the retinas from rats that had been exposed to hyperoxia and recovered in room air for 4 days. The type IV confirmed immunostaining confirmed vaso-obliteration in the deep layer of retinal vessels after hyperoxia.
Our findings of altered expression of TGF-alpha and EGF-R during retinal development suggests a biological function for this growth factor, possibly promoting retinal cell proliferation, differentiation, and survival. The altered immunolocalization of TGF-alpha and EGF-R in the hyperoxia-exposed retina suggest that TGF-alpha is likely involved in the retinal response to injury.
转化生长因子-α（TGF-α）是一种对多种不同细胞类型（包括视网膜神经元和神经胶质细胞）具有促有丝分裂作用的多肽。我们研究了TGF-α及其受体在正常和高氧暴露新生大鼠视网膜中的时空表达，以确定其表达是否与视网膜发育及对视网膜损伤的反应作用一致。
我们采用免疫组织化学方法检测出生后第1、5、10、14、18和25天的TGF-α和表皮生长因子受体（EGF-R）。为检测视网膜损伤后的TGF-α和EGF-R表达，我们研究了暴露于80%氧气10天然后在空气中恢复的大鼠视网膜。进行IV型胶原免疫定位以检测高氧后视网膜血管系统的发育。
神经视网膜中TGF-α和EGF-R的表达模式从出生后第1天的弥漫模式演变为出生后第14天的局限模式。出生后第14天，TGF-α免疫反应性与在Müller细胞中的定位一致。暴露于高氧并在空气中恢复4天的大鼠视网膜中，TGF-α和EGF-R的模式均发生改变。IV型胶原免疫染色证实高氧后视网膜血管深层存在血管闭塞。
我们发现视网膜发育过程中TGF-α和EGF-R表达改变，提示该生长因子具有生物学功能，可能促进视网膜细胞增殖、分化和存活。高氧暴露视网膜中TGF-α和EGF-R免疫定位改变提示TGF-α可能参与视网膜对损伤的反应。
