Distribution of bevacizumab in ocular tissue and its toxic effect after injection of anterior chamber / 中华实验眼科杂志

ABSTRACT

Background Bevacizumab has been widely used in the treatment of new blood vessel disease in ophthalmology.The investigation of the pharmacokinetics and safety after intracameral injection of bevacizumab can offer the basis for the management of iris neovascularization and neovascular glaucoma.Objective The present study was to observe the distribution of bevacizumab(avastin)in eye tissue and toxic effects following the injection of anterior chamber.Methods Twenty-four New Zealand albino rabbits were divided into two groups randomly.0.05 ml (1.25mg)of Bevacizumab was intracamerally injected into the left eyes in the experimental group,and a balanced salt solution of 0.05 ml was injected in the same way into the left eyes of the control group.The anterior segment of eyes and ocular fundus were examined by slit-lamp microscope and direct ophthalmoscope after injection.Intraocular pressure was measured and corneal endothelial microscopy was performed before and after the injections.Five rabbits of the two groups were sacrificed on the first day,the fourth day,the seventh day,the fourteenth day,and the thirtieth day after injection,and the eyeballs were enucleated for histopathological examination.The ultrastructure of eye tissue was observed under the transmission electron microscope on the fourth day and the thirtieth day,and then immunofluorescence staining were performed to assess the distribution of bevacizumab in the eye tissues.This experiment complied with the Regulations for the Administration of Affair Concerning Experimental Animals by State Science and Technology Commission(Version 1988).Results No abnormality in the cornea,lens,vitreous and retina was observed after the injection of bevacizumab under the slit lamp microscope and direct ophthalmoscope.No significant differences were found in intraocular pressure and corneal endothelial cell density in the bevacizumab group compared with the control group before injection and 2 hours,1 day,7 days,14 days,30 days after injection(P =0.760,P =0.956).No histopathological and ultrastructural changes of the cornea,lens,chamber angle,iris,ciliary body and retina were seen after the injection in the experimental group and control group under the light microscope and transmission electron microscope.Bevacizumab was distributed in the anterior chamber angle,iris,ciliary body,choroid and retina in injected eyes and fellow eyes after intracameral injection with red fluorescence and presented the dynamic changes with the lapse of time.The immunofluorescence response of eye tissue to bevacizumab was weaker in the fellow eyes compared with injected eyes.Bevacizumab was mainly distributed in the vessel wall and lumen.Conclusions Bevacizumab can quickly distribute in the vascular tissue of the anterior chamber angle,iris,ciliary body,choroid and retina in injected eyes after intracameral injection without obvious toxic effects to eye tissue.Bevacizumab administered intracamerally may be a new strategy or a joint strategy for iris neovascularisation.