High-resolution manganese-enhanced MRI of experimental retinopathy of prematurity
High-resolution manganese-enhanced MRI of experimental retinopathy of prematurity
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DOI：
10.1167/iovs.06-1516
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发表时间：
2007-10-01
影响因子：
4.4
通讯作者：
Gradianu, Marius
中科院分区：
文献类型：
--
作者：
Berkowitz, Bruce A.;Roberts, Robin;Gradianu, Marius
目的：验证在实验性早产儿视网膜病变（ROP）中，视网膜新生血管形成（NV）和血管迂曲与受体及受体后离子需求在空间和时间上存在独特联系这一假设。
方法：新生大鼠在室内空气（对照组）或可变氧环境（50%/10% [50/10]）中饲养。14天后，50/10组大鼠在室内空气中恢复至出生后第19天（P19）或第22天（P22）。通过ADP酶染色的视网膜整体铺片测量周边视网膜新生血管严重程度和发生率以及全视网膜小动脉和小静脉迂曲指数（TIa、TIv）。通过高分辨率锰增强磁共振成像（MEMRI）测量视网膜内离子需求和视网膜厚度。在单独的实验中，还测量了用钙通道拮抗剂地尔硫卓预处理的成年大鼠视网膜内锰摄取情况。
结果：在50/10组大鼠中，周边视网膜新生血管严重程度在P19时显著高于对照组，在P22时降低。全视网膜TIa和TIv在P19时高于对照组，但只有TIv在P22时降低。与P19时具有中心 - 周边视网膜总厚度梯度的对照组视网膜不同，50/10组视网膜的中心和周边视网膜总厚度相似。50/10组还显示周边视网膜新生血管与TIa和TIv之间存在相关性。周边视网膜内锰摄取在P19时显著超常，在P22时降低。周边视网膜内锰摄取增加与周边新生血管严重程度和全视网膜TIa相关。相反，中央受体后（而非受体）视网膜的离子需求与周边新生血管严重程度和全视网膜TIa显著相关。在任何情况下，全视网膜TIv与视网膜内离子需求均无相关性。在成年大鼠中，地尔硫卓抑制（P < 0.05）视网膜内锰摄取。
结论：本研究数据提出一种可能性，即视网膜层特异性离子需求改变导致实验性ROP中的视网膜循环异常。
PURPOSE. To test the hypothesis that in experimental retinopathy of prematurity (ROP), retinal neovascularization (NV) and vessel tortuosity have distinct spatial and temporal links with receptor and postreceptor ion demand.METHODS. Newborn rats were raised in either room air ( controls) or variable oxygen (50%/10% [50/10]). After 14 days, 50/10 rats were recovered in room air until postnatal day ( P) 19 or P22. Peripheral retinal NV severity and incidence and panretinal arteriole and venule tortuosity indexes (TIa, TIv) were measured from ADPase-stained retinal wholemounts. Intraretinal ion demand and retinal thickness were measured from high-resolution manganese-enhanced MRI (MEMRI). In separate experiments, intraretinal manganese uptake was also measured in adult rats pretreated with diltiazem, a Ca2+ channel antagonist.RESULTS. In 50/10 rats, peripheral retinal NV severity was significantly greater than in controls at P19 and was decreased by P22. Panretinal TIa and TIv were increased over control values at P19, but only TIv decreased by P22. Unlike control retinas at P19 that had a centroperipheral total retinal thickness gradient, 50/10 retinas had similar central and peripheral total retinal thickness. The 50/10 group also demonstrated a correlation between peripheral retinal NV and TIa and TIv. Peripheral intraretinal uptake of manganese was significantly supernormal at P19 and decreased by P22. Increased peripheral intraretinal retinal manganese uptake was associated with peripheral NV severity and panretinal TIa. In contrast, ion demand of central postreceptor, but not receptor, retina was significantly associated with peripheral NV severity and panretinal TIa. Panretinal TIv was not correlated with intraretinal ion demand in any case. In adult rats, diltiazem suppressed (P < 0.05) intraretinal manganese uptake.CONCLUSIONS. The present data raise the possibility that altered retinal layer-specific ion demand causes retinal circulation abnormalities in experimental ROP.