ABSTRACT
Objective To investigate the effect of tetrandrine (Tet) on experimental choroidal neovascularization and the effect of Tet on retinal structure and function. Methods Choroidal neovascularization was induced in 20 Brown Norway (BN) rats (40 eyes) by diode laser (wavelength: 810 nm; exposal time: 0.1 second; facular diameter:100 ?m; energy: 120 mW), and the rats were divided randomly into experimental and control group with 10 rats (20 eyes) in each group. In experimental group, 0.05 ml Tet with the concentration of 3.21 ?mol/L was injected intravitreously 0 and 3 days after laser photocoagulation; in the control group, the rats underwent an intravitreous injection with the same volume of sodium chloride solution. The incidence of CNV was evaluated by fundus fluorescein angiography (FFA) 14 days after laser photocoagulation. Five right eyes of another Five healthy BN rats underwent intravitreous injection with 0.05 ml Tet with the concentration of 3.21 ?mol/L, and an intravitreous injection with the same volume of sodium chloride solution was performed on the left eyes. Before injection, 1 hour, and 1 day after the first injection, and 1 hour, 1 day, 7 days, 14 days after the second injection the electroretinography (ERG) was performed on these 5 rats; 14 days after the second injection, the retinae were examined by light microscopy and transmission electron microscopy. Results The incidence of CNV was 23.26% in experimental group,which was obviously lower than that in the control group (63.33%) (P0.05). There were no structural changes of retinal tissues examined by light and electron microscopy. Conclusion Tet may inhibit choroidal neovascularization in rats; there isn′t any significant toxic effect of intravitreous injection with Tet on retina at the dosage of 3.21 ?mol/L.
ABSTRACT
Objective To investigate the retinal toxicity and verify the safe dose of intravitreal injection of nonsteroid anti inflamatory drug, diclofenac sodium. Methods Twenty eight healthy adult white rabbits were divided at random into 7 groups and received in every right eye the intravitreal injection of a single dose of diclofenac sodium solution ranging from 0.4～1.0 mg/0.1ml respectively,the left eyes were regarded as control ones. Before injection and on the 1st, 3rd, 7th, 14th, 21st, and 28th day after injection the electroretinography on both eyes was examined. On the 28th day after injection the retinas of two rabbits of every group were examined by using light microscopy. On the 10th and 30th day after injection the retinal tissues around the optic nerve disk of two eyes from every group at random were tested by using transmission electron microscopy. Results The ratio of amplitude of b wave of electroretinography in 0.4 mg and 0 5 mg groups had no significant difference from groups before injection,the retinal tissues showed no structural changes in light and electron microscopy examination. The ratio of amplitude of b wave of photoptic electroretinography in 0.6 mg groups in the early stage after injection was markedly reduced ( P