The bioimaging of acute effects on the cutaneous microcirculation by UVB exposure

目的：我们以前证明，紫外线B（UVB：波长280。315 nm）照射小鼠皮肤诱导急性微循环效应，即，血管扩张，血管通透性增加和白细胞-内皮相互作用，这是由UVB引起的活性氧引起的。本研究的目的是评估抗氧化剂，如维生素E（VE）和绿色茶儿茶素（GTC）的白细胞-内皮细胞相互作用的UVB照射（UVBIR）使用小鼠背部皮肤室（DSC）作为experimental model.METHODS：DSC被安装到雌性无毛HR-1小鼠通过手术至少72小时前的实验。我们检查了4种实验条件：仅UVBIR、抗P-选择素抗体处理+UVBIR、VE施用+UVBIR和GTC施用+UVBIR。为了观察白细胞在体内的行为，在观察之前将一剂罗丹明6 G溶液注射到尾静脉中。在UVBIR（240 mJ/cm 2）照射前后， ...更多信息 在室内的皮肤上，通过在清醒条件下使用荧光显微镜记录相同微血管的荧光图像。白细胞-内皮相互作用的离线分析是通过对每单位面积内粘附和滚动白细胞的数量计数30秒来完成的。紫外线照射前1h经饲管给予VE，每次25 μl，每日2次，共3d。GTC溶于水（10 mg/只），于UVBIR前1h经饲管给药。结果：UVBIR后6 h，微静脉中滚动白细胞数的平均值显著高于UVBIR前。当在UVBIR之前将抗小鼠P-选择素抗体注射到尾静脉中时，这种增加被抑制。当VE或GTC在UVB照射前给药时，白细胞滚动数的增加也被抑制。结论：我们的研究结果表明，抗氧化剂的管理显示出对UVB诱导的白细胞-内皮细胞相互作用的预防作用，这主要是由P-选择素介导的。少

OBJECTIVE: We previously demonstrated that ultraviolet B (UVB: wave length 280 . 315 nm) irradiation to mouse skin induced acute microcirculatory effects, i.e., vascular dilation, increase in vascular permeability and leukocyte-endothelial interaction, which was caused by reactive oxygen due to UVB. The objective of the present study was to evaluate effects of anti-oxidants such as vitamin E (VE) and green tea catechins (GTC) on leukocyte-endothelial interactions by UVB irradiation (UVBIR) using the mouse-dorsal skin chamber (DSC) as an experimental model.METHODS: DSCs were installed to female hairless HR-1 mice by surgical procedure at least 72 hours prior to the experiment. We examined 4 experimental conditions; UVBIR only, anti P-selectin antibody treatment+UVBIR, VE administration+UVBIR and GTC administration+UVBIR. To visualize the leukocytes behaviors in vivo, a bolus of rhodamine 6G solution was injected into tail vein prior observation. Before and after UVBIR (240 mJ/cm2) to th … More e skin within the chamber, fluorescent images at the same microvasculature were recorded by using a fluorescence microscopy under conscious conditions. Off-line analysis of the leukocyte-endothelial interaction was done by counting numbers adhering and rolling leukocytes within venules for 30 sec per unit area. VE was administrated twice a day (25 μl/each) for 3 days and 1 hour before the UVBIR via feeding tube. Dissolved GTC in water (10mg/each) was administrated 1 hour before the UVBIR via feeding tube. RESULTS: The mean value of rolling leukocytes number was significantly higher in the venules at 6 hours after UVBIR than that in pre-UVBIR. This increase was suppressed when anti-mouse P-selectin antibody was injected into tail vein prior to UVBIR. When VE or GTC was administrated prior to UVBIR, increase of rolling leukocytes number was also suppressed.CONCLUSIONS: Our findings suggest that the administrations of anti-oxidants show the preventive effect on UVB induced leukocyte-endothelial interaction which is mainly mediated by P-selectin. Less