Kim Young Hee, Kim Yoon Sook, Noh Hae Sook, Kang Sang Soo, Cheon Eun Woo, Park Sang Kyu, Lee Byung Ju, Choi Wan Sung, Cho Gyeong Jae
Department of Anatomy and Neurobiology, College of Medicine, Institute of Health Science, Gyeongsang National University, Chilam-dong 92, Jinju, Gyungnam 660-751, South Korea.
Exp Eye Res. 2005 Jun;80(6):753-60. doi: 10.1016/j.exer.2004.09.003.
To establish changes in phototransduction in diabetes, the effects of high glucose on rhodopsin kinase (RK) and transducin (G(t)), as well as recoverin, were examined in the retina of STZ-induced diabetic rats. Diabetes was induced by single intraperitoneal injection of STZ (50mg/kg) to Sprague-Dawley (SD) rats and the animals were sacrificed after 6 weeks. Immunohistochemistry (IHC) and Western blot analysis were carried out using antibodies against RK and G(talpha) (alpha subunit of G(t)) in the STZ-induced diabetic retina and the control retina. The expression level of recoverin protein was also analysed. In the diabetic retina, while the expression of RK protein increased, that of G(talpha) and recoverin proteins decreased. RK immunoreactivity (IR) appeared generally in the retina, and its signal increased in the outer limiting membrane (OLM), some rod cells in the outer segment layer (OSL) and at the tip of the outer plexiform layer (OPL) in the diabetic retina. G(talpha)-IR also appeared in the OPL and in photoreceptor layer. In the diabetic retina, G(talpha)-IR significantly decreased in the OPL, indicating RK-IR increase. This study illustrates the alterations in RK, G(talpha) and recoverin in the diabetic retina that may induce dysfunctions in phototransduction even in early-stage diabetes.
为了确定糖尿病中光转导的变化，研究了高糖对链脲佐菌素（STZ）诱导的糖尿病大鼠视网膜中视紫红质激酶（RK）、转导素（G(t)）以及恢复蛋白的影响。通过向Sprague-Dawley（SD）大鼠单次腹腔注射STZ（50mg/kg）诱导糖尿病，6周后处死动物。使用针对RK和G(talpha)（G(t)的α亚基）的抗体，对STZ诱导的糖尿病视网膜和对照视网膜进行免疫组织化学（IHC）和蛋白质印迹分析。还分析了恢复蛋白的表达水平。在糖尿病视网膜中，RK蛋白表达增加，而G(talpha)和恢复蛋白表达减少。RK免疫反应性（IR）普遍出现在视网膜中，在糖尿病视网膜的外限制膜（OLM）、外节层（OSL）的一些视杆细胞以及外网状层（OPL）的顶端其信号增强。G(talpha)-IR也出现在OPL和光感受器层。在糖尿病视网膜中，OPL中的G(talpha)-IR显著降低，表明RK-IR增加。本研究阐明了糖尿病视网膜中RK、G(talpha)和恢复蛋白的改变，这些改变可能即使在糖尿病早期也会导致光转导功能障碍。
