Chakrabarti S, Gan X T, Merry A, Karmazyn M, Sima A A
Department of Pathology, University of Western Ontario, London, Canada.
Curr Eye Res. 1998 Mar;17(3):301-7. doi: 10.1076/ceyr.17.3.301.5216.
Endothelins (ETs) belong to a family of vasoactive peptides implicated in several disorders of the microvasculature. In the present study, we investigated ET-1 and ET-3 peptide mRNAs and ETA, ETB receptor mRNAs in the retina of diabetic BB/W rats and age-matched, non-diabetic control animals, following six months of diabetes.
Total mRNA was extracted from each retina and was subjected to reverse transcriptase polymerase chain reaction for ET-1, ET-3, ETA and ETB. Simultaneously, beta-globin was amplified and used as a housekeeping gene. The products were analyzed on agarose gels and the specificity of the amplification was established by hybridization with amplification-specific biotinylated oligoprobes. For quantification, the products from the linear phase of amplification were subjected to serial dilution slot-blot hybridization and densitometry.
ETs and their receptor mRNA expressions were present in the retina. Retinas from the diabetic animals showed significant increases in ET-1, ET-3 ET(A), ET(B) mRNA expressions compared to those from control rats.
These findings indicate that retinal ET-1, ET-3, ET(A) and ET(B) mRNA expression in increased in the chronically diabetic BB/W rat. Augmented gene expression of ETs and their receptors potentially may be of importance in the pathogenesis of retinal microangiopathy in diabetes.
内皮素（ETs）属于血管活性肽家族，与多种微血管疾病有关。在本研究中，我们调查了糖尿病BB/W大鼠视网膜以及年龄匹配的非糖尿病对照动物在糖尿病6个月后的ET-1和ET-3肽mRNA以及ETA、ETB受体mRNA情况。
从每个视网膜中提取总mRNA，并对ET-1、ET-3、ETA和ETB进行逆转录聚合酶链反应。同时，扩增β-珠蛋白并用作管家基因。产物在琼脂糖凝胶上进行分析，通过与扩增特异性生物素化寡核苷酸探针杂交确定扩增的特异性。为了进行定量，将扩增线性阶段的产物进行系列稀释狭缝印迹杂交和密度测定。
ETs及其受体mRNA表达存在于视网膜中。与对照大鼠相比，糖尿病动物的视网膜中ET-1、ET-3、ET(A)、ET(B) mRNA表达显著增加。
这些发现表明，慢性糖尿病BB/W大鼠视网膜中ET-1、ET-3、ET(A)和ET(B) mRNA表达增加。ETs及其受体基因表达的增强可能在糖尿病视网膜微血管病变的发病机制中具有重要意义。
