[Intraocular implantation of cyclosporine A drug delivery system in the treatment of experimental uveitis].
OBJECTIVE
To investigate the effects and safety of cyclosporine A drug delivery system (CsA DDS) implanted into vitreous cavity on the treatment of experimental rabbit uveitis.


METHODS
A model of uveitis was established in 30 New Zealand white rabbits (30 eyes). The rabbits were randomized into control group (group A, 6 eyes), intravitreal non-medicated DDS group (group B, 6 eyes), oral CsA group (group C, 6 eyes) and intravitreal CsA DDS group (group D, 12 eyes). The inflammatory parameters such as floating cells, flaring and exudation in anterior chamber were graded. The cells infiltration and degree of opacity in vitreous were scored as well. The electroretinography and histopathological examination in eye, liver and kidney were recorded. In addition, CsA level in vitreous cavity was measured by HPLC in another 13 New Zealand white rabbits that received intravitreal implantation of CsA DDS.


RESULTS
Uveitis was successfully induced in the 30 eyes. The inflammation in groups A, B and C was more severe than group D. There was no significant difference between groups D and A or B (P < 0.05). The electroretinography showed more significant b-wave depression in groups A and B than group D (P < 0.05). A large amount of inflammatory cells infiltration and marked tissue disorganization were found at ciliary body and retina in groups A and B. The mean drug level in vitreous cavity ws (491.0 +/- 481.6) ng/ml at 4 weeks, (575.2 +/-0373.2) ng/ml at 8 weeks and (301.5 +/- 128.5) ng/ml at 12 weeks. No toxicity could be detected in histological examination by light microscopy.


CONCLUSIONS
Sustained therapeutic drug level could be achieved by implanting CsA DDS into vitreous cavity. It may effectively reduce the ocular inflammation in the rabbit model of uveitis.
Dong
Xiao-guang
XG
Shandong Eye Institute, Qingdao 266071, China.
Xu
Yu-mei
YM
Yuan
Gong-qiang
GQ
Shi
Wei-yun
WY
Xie
Li-xin
LX
Wang
Shen-guo
SG
D000818:Animals; D016572:Cyclosporine / Q000008:administration & dosage* / Q000493:pharmacokinetics; D016503:Drug Delivery Systems; D004343:Drug Implants; D005260:Female; D007166:Immunosuppressive Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics; D008297:Male; D011817:Rabbits; D011897:Random Allocation; D014605:Uveitis / Q000188:drug therapy* / Q000473:pathology; D014822:Vitreous Body / Q000378:metabolism
D004343:Drug Implants; D007166:Immunosuppressive Agents; D016572:Cyclosporine