Xiao M, Sastry S M, Li Z Y, Possin D E, Chang J H, Klock I B, Milam A H
Department of Ophthalmology, University of Washington, Seattle 98195-6485, USA.
Invest Ophthalmol Vis Sci. 1998 Mar;39(3):618-30.
In an unpublished study, the authors found that immunoreactivity for basic fibroblast growth factor (bFGF) is increased in rod photoreceptors adjacent to long-standing laser burns in human diabetic retinas. The goal of this study was to determine whether laser photocoagulation produces a similar increase in photoreceptor bFGF and promotes survival of these cells in dystrophic rodent retinas.
Threshold (whitening) and subthreshold (nonwhitening) laser burns were made in retinas of normal and Royal College of Surgeons (RCS) rats and normal and rds mice. The retinas were processed for immunocytochemical and morphometric analyses.
In nonlasered normal rat and mouse retinas, bFGF immunoreactivity was prominent in the nuclei of Müller cells and astrocytes. Photoreceptors were bFGF negative except for a zone of bFGF-immunoreactive rods near the ora serrata. Some photoreceptors in nonlasered retinas of RCS rats and rds mice became bFGF immunoreactive. After laser treatment, bFGF immunoreactivity was markedly increased in all photoreceptors flanking the threshold burns and within the subthreshold burns in normal and mutant rats and mice. In RCS rat retinas, photoreceptor bFGF immunoreactivity remained elevated within subthreshold burns and flanking the threshold burns, and photoreceptor survival was prolonged. In rds mouse retinas, increased bFGF immunoreactivity in photoreceptors was not sustained and their degeneration was not retarded.
Laser treatment of RCS rat retinas produced a sustained increase in bFGF immunoreactivity in photoreceptors and prolonged their survival, but laser treatment of rds mouse retinas did not have a long-term effect on photoreceptor bFGF immunoreactivity or survival. Although species differences in laser effects on photoreceptor bFGF and survival are apparent, the finding that rods flanking laser burns in human retinas have sustained increases in bFGF immunoreactivity suggests that laser treatment may be useful for prolonging survival of mutant photoreceptors in retinas of patients with retinitis pigmentosa.
在一项未发表的研究中，作者发现人类糖尿病视网膜中与长期激光灼伤相邻的视杆光感受器中碱性成纤维细胞生长因子（bFGF）的免疫反应性增加。本研究的目的是确定激光光凝是否会使光感受器中的bFGF产生类似的增加，并促进营养不良性啮齿动物视网膜中这些细胞的存活。
在正常和皇家外科学院（RCS）大鼠以及正常和视网膜变性（rds）小鼠的视网膜上进行阈值（变白）和亚阈值（未变白）激光灼伤。对视网膜进行免疫细胞化学和形态计量分析。
在未进行激光处理的正常大鼠和小鼠视网膜中，bFGF免疫反应性在 Müller 细胞和星形胶质细胞的细胞核中显著。除了锯齿缘附近有一个bFGF免疫反应性视杆细胞区域外，光感受器为bFGF阴性。RCS大鼠和rds小鼠未进行激光处理的视网膜中的一些光感受器变为bFGF免疫反应性。激光治疗后，正常和突变大鼠及小鼠中阈值灼伤两侧和亚阈值灼伤内的所有光感受器中的bFGF免疫反应性均显著增加。在RCS大鼠视网膜中，亚阈值灼伤内和阈值灼伤两侧的光感受器bFGF免疫反应性持续升高，光感受器存活时间延长。在rds小鼠视网膜中，光感受器中bFGF免疫反应性的增加未持续，其变性也未延迟。
激光治疗RCS大鼠视网膜使光感受器中的bFGF免疫反应性持续增加并延长了其存活时间，但激光治疗rds小鼠视网膜对光感受器bFGF免疫反应性或存活没有长期影响。尽管激光对光感受器bFGF和存活的影响存在明显的物种差异，但人类视网膜中激光灼伤两侧的视杆细胞bFGF免疫反应性持续增加这一发现表明，激光治疗可能有助于延长视网膜色素变性患者视网膜中突变光感受器的存活时间。
