ABSTRACT
Objective To investigate the changes of uveoscleral pathway by an I1 receptor agonist,moxonidine,and with pretreatment of antagonists topical administration,and to study the mechanism that moxonidine improves uveoscleral outflow.Methods Moxonidine was administered unilaterally and topically to rabbits and with pretreatment of the antagonists,namely,prazosin,yohimbine and efaroxan.FITC-BSA,a tracer agent,was injected into the anterior chamber after moxonidine treatment or with pretreatment of the antagonists.Frozen sections were undertaken at different time points between 2 to 10 h.Fluorescence intensity was observed in the sites of uveoscleral pathway in the sections by fluorescence microscopy.Results Bilateral fluorescence intensity treated with moxonidine was more intense than that with placebo,and the most intense regions of fluorescence were ciliary body and superchoroidal space.Fluorescence intensity by prazosin pretreatment was not significantly different compared to that by moxonidine,while yohimbine and efaroxan pretreatment decreased the intensity compared with moxonidine(P