Objective To observe the effects of high concentr at ion glucose on the calcium-activated potassium channel of rabbits′ retinal Müller cells. Methods The rabbits′retinal Müller cells were cultured in vitro under the condition of high concentration glucose, and identified by immunohistochemical staining and transmission electron microscopy. Patch-clamp technique was used to observe the changes of the calcium-activated potassium channel of retinal Müller cells caused by high concentration glucose at different time.Results High concentration glucose could inhibit the calcium-activated potassium channel of cultured retinal Müller cells in a time-dependent manner. Conclusion High concentration glucose may reduce the biological functions of Müller cells by inhibiting calcium-activated potassium channel. (Chin J Ocul Fundus Dis,2003,19:164-167)
Objective To verify the effect of Evans blue dye on determining the retina blood vessel leakage. Methods Male Sprague-Dawley rats were used in this study. The VEGF induced retinal blood vessel leakage was checked with Evans blue dye. Then the bloodretina barrier breakdown of 1 week diabetic animals was quantified with Evans blue.The dye was extracted from retina by formamide and the extraction was checked with spect rophotometer. Evans blue leakage was normalized against wet or dry retina weight. Results The retinal Evans blue content of eyes treated with VEGF was remarkably higher than that of the controls (n=17 ,Plt;0.0001). And the eyes of 1 week diabetic duration animals had more Evans blue dye than that of the normal controls (Plt;0.05). Conclusion Evans blue dye is a sensitive tracer in quantitatively diagnosing the blood retina barrier breakdown. (Chin J Ocul Fundus Dis, 2001,17:221-223)