Quantitative mapping of ion channel regulation by visual cycle activity in rodent photoreceptors in vivo.
Quantitative mapping of ion channel regulation by visual cycle activity in rodent photoreceptors in vivo.
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DOI：
10.1167/iovs.08-2958
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发表时间：
2009-04
影响因子：
4.4
通讯作者：
Gradianu M
中科院分区：
文献类型：
--
作者：
Berkowitz BA;Roberts R;Oleske DA;Chang M;Schafer S;Bissig D;Gradianu M
为了验证这样一种假设，即视网膜外部对锰的摄取程度是视觉周期活动对光感受器离子通道调节的一个定量生物标志物。对四组动物进行了研究：对照组适应于三种不同的背景光强度，暗适应对照组小鼠系统地接受视黄胺处理，暗适应小鼠在接受和不接受系统性11顺式视网膜预处理的情况下，RPE65基因外显子3(RPE65rd12)有无意义突变。所有动物均于注射锰4h后麻醉，进行MEMRI检查。根据MEMRI数据测量视网膜中央厚度和视网膜内离子通道调节。在这项研究的任何一组中，视网膜厚度没有差异(P>；0.05)。在大鼠中，外视网膜中的锰摄取量与背景光强度成反比，而内视网膜中则不然。在RPE65活性水平上的特异性抑制，无论是对视黄胺的急性抑制还是对RPE65rd12小鼠的慢性抑制，与对照组小鼠相比，视网膜外锰摄取同样减少(P<；0.05)。在RPE65rd12小鼠中，视网膜外部锰摄取在11顺式视网膜治疗后恢复正常(P>；0.05)。视网膜内摄取在视黄胺处理的小鼠中异常(P<；0.05)，但在未处理或11顺式处理的RPE65rd12小鼠中正常。目前的数据支持测量外视网膜的锰摄取程度作为体内光感受器离子通道活性的视觉周期调节的分析性非侵入性指标。
To test the hypothesis that the extent of outer retina uptake of manganese, measured noninvasively with manganese-enhanced MRI (MEMRI), is a quantitative biomarker of photoreceptor ion channel regulation by visual cycle activity. Four groups of animals were studied: control rats adapted to three different background light intensities, darkadapted control mice systemically pretreated with retinylamine, and dark-adapted mice with a nonsense mutation in exon 3 of the RPE65 gene (RPE65rd12) with and without systemic 11-cis-retinal pretreatment. In all cases, rodents were anesthetized and studied with MEMRI 4 hours after manganese administration IP. Central retinal thickness and intraretinal ion channel regulation were measured from the MEMRI data. No differences (P > 0.05) in retinal thickness were noted within any arm of this study. In rats, manganese uptake was inversely proportional to the background light intensity in the outer retina but not in the inner retina. Specific inhibition at the level of RPE65 activity, either acutely with retinylamine or chronically in RPE65rd12 mice, similarly reduced (P < 0.05) outer retinal manganese uptake compared with that in control mice. In RPE65rd12 mice, outer retinal manganese uptake returned to normal (P > 0.05) after 11-cis retinal treatment. Inner retinal uptake was supernormal (P < 0.05) in retinylamine-treated mice but normal in untreated or 11-cis treated RPE65rd12 mice. The present data support measuring the extent of manganese uptake in the outer retina as an analytic noninvasive metric of visual cycle regulation of photoreceptor ion channel activity in vivo.
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影响因子：
4.8
作者：
Ablonczy, Z;Crouch, RK;Rohrer, B
通讯作者：
Rohrer, B
影响因子：
3.5
作者：
Ohguro, H;Ohguro, I;Nakazawa, M
通讯作者：
Nakazawa, M
影响因子：
4.4
作者：
Berkowitz, Bruce A.;Roberts, Robin;Vingrys, Algis J.
通讯作者：
Vingrys, Algis J.
影响因子：
4.4
作者：
Berkowitz, Bruce A.;Roberts, Robin;Luan, Hongmei
通讯作者：
Luan, Hongmei
影响因子：
4.4
作者：
Calkins, David J.;Horner, Philip J.;Berkowitz, Bruce A.
通讯作者：
Berkowitz, Bruce A.