ABSTRACT
Objective To observe the effects of the topical benzalkonium chloride on the cornea of experi-ment animals and evaluate the safety of topical benzalkonium chloride.Methods 36 rabbits were randomly divided into two groups according to the random number table,18 rabbits(36 eyes)in each group.The benzalkonium group was assigned as preservative benzalkonium chloride(0.05%)gutta,the control group was served as blank control. Rabbits were examined by the slit lamp,non-contact corneal endothelial microscope and Ultrasonic Wave instrument for corneal endothelial cell density and corneal thickness before and the 3rd weeks,the 6th weeks after the medica-tion.In vitro cornea was stained by typan blue and alizarin red,corneal endothelial cells were observed and calculate the viability of corneal endothelial cells (CECs).Results The differences of corneal thickness at the 3rd weeks and the 6th weeks were not statistically significant between the two groups(t =1.876,1.876,all P >0.05);The differ-ences of the corneal endothelial cell density and the viability of corneal endothelial cells(CECs)between the two groups at the 3rd weeks and the 6th weeks were not statistically significant(t =0.321,1.541,all P >0.05);The tear meniscus height of the benzalkonium group were lower than the control group at the 6th weeks[(142 ±36)μm vs. (198 ±31)μm,t =2.462,P <0.05].Conclusion Benzalkonium chloride has no impact on the corneal endothelial cells in short period,but the affection on the tear is obvious.
ABSTRACT
ObjectiveTo observe the morphology of the uveoscleral pathway following topical Prazosin（PZ） in rabbit free-sympathetic eyes．MethodsThe one lateral superior cervical ganglionectomy（SCG） were preformed on each rabbit．PZ drops were installed only on the SCG eyes on 14 days Postoperationly．Microamounts of fluorescein isothiocyanate-bovine serum albumin（FITC-BSA） was infused into anterior chamber of rabbit eyes as the teacer，two rabbits in each group were killed at 2，4，6，8，10，and 12h after PZ instillation．Degress of fluorescent intensity of ciliary body，suprachoroidal space，anterior and posterior sclera，and choroid were observed under fluorescence microscopy．ResultsThe IOP of the SCG eyes was lower after installation of PZ．But the reduced extent is below that of normal rabbit eyes；After installation of PZ，the fluorescent intensity of the ciliary body，suprachoroidal space，anterior and posterior sclera，and choroid was less stronger than the control eyes，but fader than at the same area of the normal eyes obviously．ConclusionThe outflow effects of PZ drops on increasing uveoscleral pathway were obviously decreased in the SCG eyes．It depends on the activity of sympathetic nerve system partially．Besides，there are other mechanisms．
ABSTRACT
It is to discuss the method for studying uveoscleral pathway and the influence of uveoscleral outflow on aqueous humor drainage. Seventeen rabbits were randomly divided into the flow group that included 5 rabbits and the morphological group that included 12. Fluorescein-isothiocyanate bovine serum albumin (FITC-BSA) was perfused into anterior chambers of flow group rabbit eyes as the tracer for measuring uveoscleral outflow. This tracer was infused into anterior chambers of morphological group rabbit eyes for observing fluorescent intensity of all tissue of the uveoscleral pathway with fluorescence microscopy. Fluorescence was seen in all sites of uveoscleral pathway. The fluorescent intensity of ciliary body and suprachoroidal space was significantly stronger than that of anterior sclera (P＜0.05). The intensity of choroid and posterior sclera was significantly weaker than that of other tissues (P＜0.05). The average value of uveoscleral outflow was (0.18±0.031) μl/min. This study demonstrates that uveoscleral pathway plays an important role in aqueous humor drainage. Anterior sclera is the main site where aqueous humor flows out. FITC-BSA is an effective tracer for studying uveoscleral pathway from both morphological and functional aspects.