血-视神经屏障特性研究进展

血眼屏障有血-房水屏障,血-视网膜屏障,这些特殊结构对防止眼免疫性炎症和损伤过程的发生起到了重要作用.迄今为止,血-视神经屏障(blood-optic nerve barrier)的概念国内外教科书中几无描述,本文就有关血-视神经屏障特性的研究进行综述.     

青光眼小梁切除术后早期血-房水屏障的变化

目的　观察青光眼小梁切除术对血 房水屏障的影响。方法　 16例 19眼非继发于剥脱综合征的青光眼患者全部行小梁切除术 ,分别测量术前、术后第 2、4、7天房水闪辉值及眼压。结果　小梁切除术前、术后第 2、4、7天房水闪辉值分别为 15 .0 5 0± 10 .346、30 .5 80± 2 1.4 35、2 1.72 0± 2 0 .0 6 1、16 .5 80± 12 .880 ,术前与术后第 2天、术后第 2天与第 7天的房水闪辉值不同 (P =0 .0 0 6、0 .0 12 ) ;术前与术后第 4天、第 7天的房水闪辉值之间无显著性差异 (P =0 .2 2 6、0 .781) ;术后第 2天与第 4天、术后第 4天与第 7天房水闪辉值亦无显著性差异 (P =0 .10 9、0 .35 0 )。术前、术后第 2天、第 4天、第 7天患眼眼压分别为 (2 3.2 95± 9.313)mmHg、(19.94 7±9.36 3)mmHg、(14 .6 79± 6 .4 19)mmHg、(13.36 8± 4 .95 5 )mmHg(1kPa=7.5mmHg) ,各时间点眼压与房水闪辉值之间无线性相关性 (P =0 .774、0 .5 2 8、0 .76 1、0 .739)。各型青光眼术前的房水闪辉值有差异 (P =0 .0 4 1<0 .0 5 ) ,术后各观察时间各型青光眼的房水闪辉值无明显差异 (P =0 .5 75、0 .4 84、0 .2 97>0 .0 5 )。结论　青光眼小梁切除术后早期血 房水屏障破坏 ,但这种破坏可以在短时间内恢复     

丹参通过糖尿病小鼠血-眼屏障与防治视网膜病变实验研究

目的 建立诱发小鼠糖尿病视网膜病变（d iabetic retinopathy,DRP）模型,观察疾病的发生发展病理变化,探讨中药丹参在改善DRP中的表达及防治并阐明其作用。方法 选用动物高脂肪含量的饲料喂养以单基因遗传自然发病型的糖尿病鼠进行动物活体实验,随机应用中药高中低不同剂量治疗后的糖尿病小鼠与正常小鼠视网膜组织表达进行检测并进行光学显微镜对照观察。结果 显示糖尿病小鼠视网膜内丛状层和视细胞层增厚明显,排列紊乱渗漏增强,不同剂量的丹参对小鼠糖尿病视网膜的改变表现不同。结论 糖尿病可使小鼠血-视网膜屏障受损,丹参能改善实验性DRP的影响及可能的作用机制。     

冰片对血眼屏障通透性的影响

目的:研究冰片对家兔血眼屏障通透性的影响。方法:将42只家兔随机分为实验组和对照组,每组21只。实验组给予冰片(0.8g/kg)灌胃,对照组等体积溶媒灌胃,给药后15min耳缘静脉注射20g/L伊文思蓝(EB),分别经5,15,30,45,60,90,120min取房水及玻璃体。采用荧光分光光度法检测房水及玻璃体中的EB浓度。结果:与对照组相比,实验组房水和玻璃体中EB含量更高。结论:冰片可提高家兔血眼屏障的通透性,是一种有效促进药物透过血眼屏障的穿透促进剂。这将为某些内眼疾病的药物治疗提供新方法。     

眼挫伤的血—房水屏障改变

目的 探讨外伤性葡萄膜炎与血－房水屏障破坏的关系。方法 新西兰兔１８只,以自由落体打击力制备双眼重型闭合性眼球挫伤模型;以＾１３１Ｉ为示踪剂进行房水免疫学测定。并与正常兔眼作对照。结论 兔眼钝伤后可致较严重的血－房水屏障破坏。伤后１周为快速修复期,４周时完全修复。     

曲安奈德术中眼内注射对血眼屏障的保护作用

目的评价术中玻璃体腔内注射曲安奈德(triamcinolone acetonide)对复杂的玻璃体视网膜手术术后血眼屏障的保护作用。方法11例(13眼)复杂的玻璃体视网膜手术,手术结束后,将曲安奈德混悬液注入玻璃体腔内,在硅油填充眼,曲安奈德的注入量为0.05mL(2mg),非硅油填充眼为0.1mL(4mg)。手术后随访2~4月,观察曲安奈德颗粒的消失时间、抗炎效果和并发症。结果曲安奈德颗粒从眼内消失的时间,硅油填充眼为2~3月,非硅油填充眼为1~1.5月。术后均未出现明显的早期眼部炎症反应。眼压升高2眼,1眼由硅油引起,另1眼发生在手术后4月,由葡萄膜炎引起。无与曲安奈德相关的并发症发生。结论对复杂的玻璃体视网膜手术,术中玻璃体腔内注射曲安奈德可有效地防止血眼屏障破坏,减轻手术后眼部炎症反应。     

中药有效成分在血-眼屏障通透性及促透方法的研究进展

血-眼屏障( blood-eye barrier,BEB)是机体维持眼内环境稳定的重要结构之一,但同时也是药物治疗内眼疾病的主要制约因素。传统中药能调节人体生理功能,且毒副作用较低,对治疗内眼疾病有独特的优势。本文结合国内外文献报道,对BEB的特性作简要概括,并重点综述中药及其有效成分在 BEB 通透性及促透作用的研究进展。     

糖尿病视网膜病变血-视网膜屏障的损伤机制

糖尿病严重影响了视网膜微循环,从而引起一系列组织结构的病理改变.这些改变最终可导致内皮细胞过度增生,血管通透性改变,异常的视网膜血管形成并发视力减退.本文阐述了高血糖对视网膜微血管系统的影响,从细胞功能和分子生物学的角度阐明高血糖所导致的细胞损伤效应.高血糖可通过影响细胞连接功能、诱导细胞凋亡以及改变细胞间的相互作用等方式对视网膜血管细胞造成损伤.这将为人们了解糖尿病视网膜病变发生发展中的分子及细胞缺陷提供新思路.     

巩膜扣带术后早期泪膜变化的临床研究

目的观察巩膜扣带术后早期泪膜变化的临床特征及其规律。方法收集2009年3月至7月行巩膜扣带术的裂孔源性视网膜脱离的连续临床病例36例(36眼)。于术前1d,术后1d、3d、10d、1个月及3个月进行症状评分、泪膜破裂时间(break-up time,BUT)测定、角膜荧光素染色(corneal fluorescein staining,CFS)及基础泪液分泌试验(Schirmer I test,SIT)等检查,以对侧眼作为自身对照,根据临床检查结果进行评分并进行统计学分析。结果术眼:术后1d、3d,70%患者术眼出现疼痛、发痒、红肿及流泪等不适症状;BUT术后10d与术前相比平均增加5.35s,差异有显著统计学意义(P=0.001),术后3个月时80%患者泪膜趋于正常;CFS评分在术后1d减少最明显,与术前1d比较差异有显著统计学意义(Z=-4.038,P=0.001);SIT术后1d增加最明显(P=0.001),50%患者泪液分泌量大于30mm,70%患者泪液分泌量大于25mm,术后10d恢复至术前水平。对照眼:术后未出现眼部不适症状;BUT术后10d、1个月、3个月分别为(8.33±5.45)s、(8.44±4.70)s、(8.75±3.71)s,与术前比较,差异均有统计学意义(均为P<0.05);SIT术后1d,17%患者泪液分泌量大于25mm,与术前比较,差异有统计学意义(P<0.05)。术眼与对照眼组间比较,干眼不适症状、BUT和SIT在术后1d、3d差异均有统计学意义(均为P<0.05),CFS评分术前1d、术后1d、3d、10d差异均有统计学意义(Z=-4.247、-3.174、-2.528、-1.555,均为P<0.05)。结论巩膜扣带术后早期可出现明显眼表不适症状,并影响泪液分泌及泪膜稳定性,术后3个月时术眼眼表及泪膜基本趋于稳定。     

激光蛋白细胞检测仪在葡萄膜炎中的应用价值

目的:探讨激光蛋白细胞检测仪(laser flare cell meter,LFCM)定量测定葡萄膜炎患者房水闪辉的临床应用价值。方法:选择2009-07/2010-07在我院就诊、复查的葡萄膜炎患者129例171眼,根据其临床特点将其分为前葡萄膜炎组87例87眼,中间葡萄膜炎组10例20眼,后葡萄膜炎组32例64眼;正常对照组50例100眼。应用LFCM(FM-600型)检测各期患者房水闪辉情况,检查前所有患者均经裂隙灯显微镜检查,并进行房水闪辉分级。结果:前葡萄膜炎患者裂隙灯检查前房闪辉48眼(1+),35眼(2+),2眼(3+),2眼(4+);LFCM检测1～2级房水闪辉的平均值分别为28.6±6.7pc/ms,144.3±28.1pc/ms,3～4级房水闪辉由于背景干扰大,检测结果显示警告或无法检测;前葡萄膜炎患者1～2级房水闪辉的裂隙灯显微镜检查与LFCM测定结果呈正相关(r=0.901,P<0.01);与对照组房水闪辉值比较(5.1±1.8pc/ms),差异具有统计学意义(P<0.05)。中间葡萄膜炎患者裂隙灯检查前房闪辉10眼(1+),10眼(2+),LFCM检测1～2级房水闪辉的平均值分别为31.7±5.0pc/ms,130.7±12.9pc/ms;中间葡萄膜炎患者1～2级房水闪辉的裂隙灯显微镜检查与LFCM测定结果呈正相关(r=0.867,P<0.01);与对照组房水闪辉值比较,差异具有统计学意义(P<0.05)。后葡萄膜炎患者裂隙灯检查前房闪辉均为0级,LFCM检测房水闪辉的平均值为9.8±3.1pc/ms,高于对照组,差异具有统计学意义(P<0.05)。结论:LFCM(FM-600型)可确切判断葡萄膜炎患者轻、中度的血-房水屏障破坏,对判断眼前段炎性反应和指导临床治疗有重要意义。     

准分子激光原位角膜磨镶术对血-房水屏障功能的影响

目的 :评价准分子激光原位角膜磨镶术 (LASIK)对血 房水屏障功能的影响。方法 :对河南省眼科研究所行LASIK手术的 2 0例 (38眼 )屈光不正患者在手术前 1d及手术后 1d、1w分别行激光闪辉 /细胞光度仪 (KowaFC 2 0 0 0 )检查 ,测定房水闪辉光度值和细胞数 ,观察其数值变化 ,以判断LASIK手术对血 房水屏障功能的影响。结果 :手术前及手术后 1d、1w的房水闪辉光度值分别为 (3.5 3± 1.33)ph/ms、(4 .17± 1.2 4 )ph/ms和 (3.6 2± 1.34)ph/ms,细胞数分别为 (0 .31± 0 .6 1)个 /mm3 、(0 .2 4± 0 .34)个 /mm3 和 (0 .2 2± 0 .5 4 )个 /mm3 ,手术前后差异均无显著性 ,P >0 .0 5。结论 :LASIK手术安全可靠 ,对血 房水屏障无明显影响。     

房水闪辉和细胞的定量测量

激光蛋白细胞检测仪可快速、精确、定量测定房水蛋白浓度和细胞数量,评价各种眼内疾病、手术和治疗对血-房水屏障功能的影响,对疾病的诊断和疗效观察提供有利帮助,本文就其在临床上的应用作一综述。     

Effects of subconjunctival methylprednisolone on the blood aqueous barrier following cataract surgery

The aim of this double-blind randomized study was to assess the effect of subconjunctival methylprednisolone hemisuccinate (MH) on the recovery of the blood aqueous barrier (BAB) following uncomplicated cataract surgery performed by the same surgeon in normal eyes. Fifty eyes of fifty patients (28 female, 22 male, mean age 72.3 ± 11.2 years) were randomized into two groups: group 1 received a subconjunctival injection of MH (40 mg in 0.5 cc) at the end of the surgery and group 2 did not. All patients were free of other ocular or systemic diseases known to alter the BAB and were not taking any anti-inflammatory medications. Postoperative treatments were similar in both groups. The patients were submitted to laser flare photometry 30 minutes to one hour after mydriasis with a drop of tropicamide preoperatively and on the first, second and seventh day and then one month and six months following surgery. No difference in aqueous flare was seen between the two groups on any of postoperative visits. These data suggest that subconjunctival MH has no beneficial effect in postoperative BAB permeability following uncomplicated cataract surgery in normal eyes.Presented in part at ARVO Meeting 1994 (Sarasota, Florida, USA)     

Mechanism of a model dipeptide transport across blood-ocular barriers following systemic administration

The purposes of this study were to provide functional evidence for the presence of a peptide transporter on blood-ocular barriers and to elucidate the mechanism of a dipeptide transport across these barriers following systemic administration. Glycylsarcosine was chosen as a model dipeptide and [(3)H] glycylsarcosine was administered through the marginal ear vein of New Zealand white rabbits. At the end of an experimental period, vitreous humor, retina and aqueous humor were collected. Time dependent uptake of glycylsarcosine into ocular tissues was studied at 5, 10, 15 and 30 min. Competitive inhibition studies were performed by intravenous administration of [(3)H] glycylsarcosine with and without various inhibitors. Concentration-dependent ocular uptake of glycylsarcosine was carried out by administration of various concentrations of unlabelled glycylsarcosine spiked with a fixed amount of [(3)H] glycylsarcosine. Time-dependent uptake of glycylsarcosine into vitreous humor, retina and aqueous humor for a period of 30 min following systemic administration was linear. Ocular uptake of glycylsarcosine was inhibited by peptide transporter substrates such as dipeptides (glycylproline and carnosine) and captopril but not by non-substrates such as amino acids. Concentration-dependent self-inhibition of glycylsarcosine ocular uptake was also observed. The results indicate that model dipeptide is transported across blood-ocular barriers via a carrier-mediated process. In conclusion, an oligopeptide transport system is involved in the transport of glycylsarcosine across blood-ocular barriers. This information may be utilized to design transporter/receptor targeted drug delivery systems for efficient ocular uptake from systemic administration.     

眼前节内眼模拟手术诱发血眼屏障破坏的大鼠动物模型

目的 建立眼前节内眼模拟手术诱发血眼屏障破坏的大鼠动物模型。方法 清洁级健康成年雄性Sprague-Dawley大鼠150只,随机分为对照组和模型组,每组75只。按1 ml/kg的剂量腹腔注射盐酸氯胺酮 盐酸甲苯噻嗪混合液麻醉大鼠。磷酸盐缓冲液灌注袋连接三通管。三通管一端连接24G静脉留置针,手术显微镜下在3点时钟位从角巩缘前透明角膜30°斜行穿刺入前房,退出针头,留置套管;另一端连接24G静脉留置针套管,与测压计相连测量大鼠眼压。大鼠眼压波动于0～12 mm Hg（1 mm Hg=0.133 kPa）之间,波动30 次/min,重复60 次。采用氧氟沙星滴眼液滴眼。建模后第1、2、3、5、7天,采用免疫组织化学法检测大鼠白蛋白;定量检测大鼠房水、视网膜中伊凡思蓝（EB）浓度。结果 免疫组织化学染色结果显示,建模后第1、2、3、5、7天对照组白蛋白阳性染色均局限于虹膜和视网膜血管内,脉络膜弥漫性着色。建模后第1天,模型组白蛋白阳性染色主要位于虹膜和视网膜神经层血管周围;建模后第2、3天,阳性染色扩散到虹膜和视网膜全层;建模后第5、7天,阳性染色主要局限于虹膜和视网膜血管内。模型组房水中EB浓度在建模后第1、2、3、5天,均较对照组高（t=25.781,37.433,25.150,19.171;P＜0.01）;建模后第7天,与对照组接近（t=1.303,P=0.209）。模型组视网膜EB浓度在建模后第1、2、3天,均较对照组高（t=11.997,14.622,23.014;P＜0.01）;建模后第5、7天,与对照组接近（t=2.027,0.756;P=0.058,0.459）。结论 通过模拟眼前节内眼手术损伤因素,可建立内眼手术诱发的血眼屏障破坏的大鼠动物模型。     

Efficacy and safety of indomethacin 0.1% eye drops compared with ketorolac 0.5% eye drops in the management of ocular inflammation after cataract surgery

Purpose: To determine whether indomethacin 0.1% eye drops are at least as effective as ketorolac 0.5% eye drops in treating ocular inflammation following cataract surgery. Methods: Prospective, multicenter, investigator‐masked, parallel‐group, randomized, active‐controlled clinical trial. Cataract patients were randomized in a 1:1 ratio to receive indomethacin or ketorolac administered QID for 3 weeks beginning 1 day before surgery. The primary end‐point was aqueous flare measured by laser flare meter at postoperative Days 1 and 7. Secondary end‐points included retinal thickness, slit lamp and funduscopic examinations and postsurgical pain ratings. Safety and tolerability were also assessed. Results: A total of 86 patients were included in the per protocol population (n = 43 per treatment group). Indomethacin was found non‐inferior to ketorolac for comparison of aqueous flare at postoperative Days 1 and 7 (Day 1: 95% CI: ?2.37, 5.50; non‐inferiority upper margin, 15 ph/ms and Day 7: 95% CI: ?7.83, ?0.94; non‐inferiority upper margin, 8 ph/ms) and statistically better than ketorolac at Day 7 (p = 0.013). There were no significant between‐group differences in aqueous flare and change from baseline in retinal thickness at postoperative Days 30 and 90. Indomethacin showed a higher subjective tolerance rating than ketorolac at postoperative Days 7 and 30 (p ≤ 0.044). Conclusion: Indomethacin 0.1% was at least as effective as ketorolac 0.5% at Day 1 and more effective than ketorolac 0.5% at Day 7 in treating ocular inflammation after uncomplicated cataract surgery. Indomethacin was better tolerated than ketorolac. There were no clinically meaningful safety concerns with either treatment.