Evaluation of the effect of fasudil hydrochloride on outflow facility in enucleated eyes of different animals / 眼科新进展

Objective To evaluate the influence of a selective Rho-associated protein kinase inhibitor (fasudil hydrochloride) on outflow facility in enucleated porcine,rabbit and bovine eyes.Methods At the constant perfusion pressure of 15 mm-Hg (1 kPa =7.5 mmHg),the baseline coefficient of outflow facility (C0) of the isolated porcine,rabbit and bovine eyes was recorded respectively.The enucleated porcine eyes were divided into two groups randomly (n =6),and they were control group and experimental group.The same grouping method was also used-C0 the ribbit and bovine eyes.The control group was subjected to GPBS perfusion,while the experimental group was treated with 100 μmol · L-1 fasudil solution,followed by recording the experimental coefficient of outflow facility (C1),as well as calculating ΔC (ΔC =C1-C0) and ΔC％ (ΔC％ =ΔC/C0).Finally,the paired t test and one-way analysis of variance were performed using SPSS 17.0.Results As for porcine eyes,the ΔC％ of the control group was (17.83 ± 3.84) ％ while the experimental group was (44.00 ± 6.44) ％;as for rabbit eyes,the ΔC％ of the control group was (15.50 ± 2.93) ％,while the experimental group was (31.67 ±6.54)％;as for bovine eyes,the ΔC％ of the control group was (11.67 ± 1.17)％,while the experimental group was (37.17 ± 4.48)％.The ΔC％ in the experimental group was significantly increased when compared with the control group in three animals,with significant difference (all P ＜ 0.05).There was no statistical difference in ΔC％ of three experimental groups among different kinds of animals (all P ＜ 0.05).Conclusion Fasudil can improve outflow facility in enucleated eyes of animals,and it can redistribute aqueous humor drainage to a wider area through directly regulating the cytoskeleton of cells and matrix,resulting in increased coefficient of outflow facility.

Fluorophotometric measurements of aqueous-humor flow in post-YAG laser iridotomy for acute angle closure

Objective@#This study compared the rates of aqueous-humor flow and trabecular outflow in eyes that had undergone YAG laser iridotomy (LI) for primary-acute-angleclosure (PAC) attack and primary-angle-closure suspect (PACS).@*Methods@#Patients who had PAC attack in one eye and narrow occludable angles (PACS) in the other eye that had undergone YAG LI were recruited. All underwent complete ophthalmologic examination including gonioscopy, ultrasonic pachymetry, A scan, and fluorophotometry to determine the rate of aqueous-humor flow. The Goldmann equation was used to compute the outflow facility using the values of aqueous flow and intraocular pressure (IOP).@*Results@#Fifty eyes of 25 patients were included, 25 of which had PAC attack and 25 were PACS. The central corneal thickness (CCT), anterior-chamber depth, and anterior-chamber volume of the 2 groups were comparable. PAC-attack eyes had significantly higher IOP (18.4 mm Hg) than the PACS (14.12 mm Hg) (p = 0.001). The mean rate of aqueous flow was 2.50 ± 0.94 µL/min and 2.89 ± 1.17 µL/min in the PAC and PACS respectively (p = 0.20). The mean aqueous-outflow facility was 0.29 ± 0.18 µL/min and 0.59 ± 0.37 µL/min respectively (p = 0.0008).@*Conclusion@#A significantly lower aqueous-outflow facility was demonstrated by fluorophotometry among eyes with PAC. Despite the anatomically open angles, they continued to have higher IOPs.

Relationship between the rabbit glucocorticoid receptor and steroid-induced glaucoma / 眼科新进展

Objective　To study the correlation between the rabbit glucocorticoid receptor(GR) and steroid-induced glaucoma(SIG).Methods　The GR binding in peripheral blood leukocytes and plasma cortisol were measured in 15 adults pigmented rabbits on the first day of experiment, 0.5mg dexamethasone was injected in the right eyes of each rabbit once every 2 days, totally 15 times for 30 days. Right eyes intraocular pressure(IOP) and aqueous outflow facility were measured every week, the relation between GR, plasma cortisol, IOP and aqueous outflow facility(C) was analyzed. Results　After the experiment the IOP increased by 0.67kPa±0.49kPa(P＜0.01),C decreased by 0.08±0.11(P＜0.01).GR may closely be related to IOP and C(r=0.56,P＜0.025; r=0.60,P＜0.01).Plasma cortisol was independent of IOP and C(r=0.27, P＞0.05;r=0.34,P＞0.05).Conclusion　The level of GR has positive correlation with the sensitivity of tissue of eye to glucocorticoid.

The Effect of Lens on the Contractability of Ciliary Muscle

There are many factors affecting the outflow facility. Structural changes of aqueous outflow channel by ciliary muscle contraction play major role in the control of outflow facility. Although many studies on the physiology of outflow facility have been done by many authors, the lens effect on the ciliary muscle contractability has not been reported. We performed clear corneal phacoemulsification and foldable intraocular lens implantation in 42 cataract patients and measured intraocular pressure(IOP) pre and postoperatively by Goldmann applanation tonometer and determined outflow facility with and without 2% pilocarpine before and after cataract surgery, respectively. We analysed IOP changes after surgery, and assessed ciliary muscle contractability by analysing outflow facility changes. Statistical analysis was done by Wilcoxon`s signed rank test. IOP decreased by 2.4+/-0.4mmHg(mean+/-SEM)(P<0.001): outflow facility with and without pilocarpine increased by 0.080+/-0.012microliter/min/mmHg(P<0.001) and 0.045+/-0.006microliter/min/mmHg(P<0.01), respectively after lens extraction: outflow facility increased 2.8+/-0.4 times by pilocarpine itself after lens extraction(P<0.001). The lens connected to the ciliary muscle muscle by zonnule may have an influence on ciliary muscle contractability.

The Effect of Endothelin-1 on IOP and Aqueous Outflow Facility in the Rabbit Eye

Endothelin(ET) is known as a family of potent hydrophobic, vasoactive peptide. We investigated the effect according to the concentrations of ET on intraocular pressure(IOP), aqueous outflow facility, pupillary diameter and light reflex and iris vessels. Twenty-four hours after injection of 2.5 microgram and 10 microgram of ET-1 into the anteriorvitreous of rabbit eyes, the IOP was reduced by 69% and 80%, respectively and did not return to the level of prefreatment until at least 14 days and 20 days, respectively. But the decrease of IOP was not due to the increased aqueous outflow. The pupillary diameter of ET-1 treated eyes was 1 to 2mm larger than the pretreatment. The time course of the pupillary effects generally ran paralled with the reduction of IOP. The iridial and conjunctival hyperemia was detectable during the pupillary dilatation. Endothelins are therefore potential participants in the local regulation of IOP, ocular blood vessel tone, and iris smooth muscle tone.