眼调节对葡萄膜巩膜房水外流途径影响的形态学观察

目的　通过形态学观察探讨眼调节对葡萄膜巩膜房水外流途径的影响。方法　14只健康日本大耳白兔，10只（20眼）用于荧光显微镜观察，4只（8眼）用于光镜观察，按用药方法不同各分为调节状态组和非调节状态组。所有白兔双眼分别采用5 g·L^-1硝酸毛果芸香碱滴眼液和10 g·L^-1盐酸环喷托酯滴眼液模拟眼调节态和非调节态，测量滴眼前及末次滴眼后30 min的眼压,于滴眼后30 min将5 μL异硫氰酸荧光素标记牛血清白蛋白（FITC-BSA）注入前房，于前房注射后0.5 h、1.5 h、2.5 h、3.5 h、4.5 h各处死2只白兔，摘取双眼作冰冻切片，于荧光显微镜下观察调节态和非调节态葡萄膜巩膜途径的房水荧光强度及其分布形态；于滴眼后30 min处死4只白兔，摘取双眼通过HE染色和抗平滑肌抗体染色在普通光镜下观察兔眼睫状肌形态、肌间隙。结果　调节状态组基线眼压（19.13±1.75）mmHg（1 kPa=7.5 mmHg)，毛果芸香碱模拟眼调节后眼压下降，滴眼后眼压为（16.56±1.67）mmHg，差异有统计学意义（t=9.37，P=0.00)。调节状态组睫状体、脉络膜上腔和前巩膜荧光强度较非调节状态组均显著减弱（均为P<0.05），而两组间后巩膜、脉络膜差异均无统计学意义（均为P＞0.05）。光镜观察见非调节状态组放射肌区域有明显肌间隙，而在调节状态组未发现此间隙。结论　眼调节可通过收缩睫状肌从而减少房水从葡萄膜巩膜房水外流道排出。

Effects of ocular accommodation on the morphological change of uveoscleral outflow pathway in Albino rabbits

Objective　To explore the influence of accommodation on the pathway of uveoscleral aqueous outflow through morphological observation.Methods　Fourteen healthy Japanese big-eared white rabbits, of which 10 (20 eyes) were used for fluorescence microscope observation, and 4 (8 eyes) were used for light microscope observation.According to different medication methods, they were divided into two groups: accommodation group and non accommodation group. All rabbits were treated with 5 g·L^-1pilocarpine eye drops and 10 g·L^-1cyclopentolate hydrochloride eye drops to simulate the accommodative and non-accommodative states, and the intraocular pressure (IOP) before and 30 minutes after the last eye drop were measured.After 30 minutes, 5 μL of fluorescein isothiocyanate bovine serum albumin (FITC-BSA) was injected into the anterior chamber. Two rabbits were killed after 0.5 hour, 1.5 hours, 2.5 hours, 3.5 hours and 4.5 hours after anterior chamber injection, and their eyes were taken for frozen section. The fluorescence intensity and its distribution of uveoscleral pathway were observed under fluorescence microscope.Four rabbits were sacrificed 30 minutes after the eye drops, and the morphology and space of ciliary muscles were observed by HE staining and anti smooth muscle antibody staining.Results　The results showed that the baseline IOP was (19.13±1.75) mmHg (1 kPa=7.5 mmHg), and the IOP was (16.56±1.67) mmHg after accommodation using pilocarpine (t=9.37,P=0.00).The fluorescence intensity of ciliary body, suprachoroidal cavity and anterior sclera in the accommodation group were significantly lower than those in the non accommodation group (all P<0.05), but there was no significant difference in the posterior sclera and choroid between two groups (all P>0.05). Light microscopy showed that there was obvious muscle space in the radiated muscle area in the non accommodation group, but not in the accommodation group.Conclusion　Ocular accommodation may contract ciliary muscle to decrease uveoscleral outflow.