Abstract
Purpose :
To demonstrate the functional changes of the retina monitored by ERG in a rat retinal ischemia model, which is for screening new therapies of retinal degeneration.
Methods :
12 Brown Norway male rats were randomized by body weight into 2 groups, 6 animals per group. After animals were sedated on Day 0, lateral conjunctival peritomy and disinsertion of the lateral rectus muscle were performed on the right eye per animal in Group 2 and the optic nerve sheath was exposed by blunt dissection and ligated with a 6-0 nylon suture until retinal vessel blood flow ceases (ischemia), as visualized by the operating microscope. After 60 minutes, the suture was removed. The same procedure was performed on the right eyes in Group 1 without ligation of the optic nerve sheath. The left eyes in all groups had no procedure and as the contralateral eyes. On Day 28, Dark and Light adapted ERG was performed on both eyes at all eyes at all animals.
Results :
In the Group 2, the mean b-wave of 32.61 (µv) in the right eyes was reduced compared to 155.27(µv) in the left eyes in the Dark Rod Response; the mean b-wave of 45,57 (µv) in the right eyes was reduced compared to 238,80 (µv) in the left eyes in the Dark Maximal Response; the mean Peak-wave of 12.66 (µv) and the mean Trough-wave of -7.29 (µv) in the right eyes were reduced compared to 88.64 (µv) and -35.54 (µv), respectively, in the left eyes in the Dark Oscillatory Potential; the mean b-wave of 23.66 (µv) in the right eyes was reduced compared to 129.47 (µv) in the left eyes in the Light Single White Flash; and the mean Peak-wave of 4.82 (µv) in the right eyes was reduced compared to 22.70 (µv) in the left eyes in the Light 30 Hz Flicker. In the right eyes, the mean b-wave of 32.61 (µv) in Group 2 was reduced compared to 172.12 (µv) in Group 1 in the Dark Rod Response; the mean Peak-wave 12.66 (µv) in Group 2 was reduced compared to 62.09 (µv) in Group 1 in the Dark Oscillatory Potential; the mean b-wave of 23.66 (µv) in Group 2 was reduced compared to 92.43 (µv) in Group 1 in the Light Single White Flash; and the mean Peak-wave of 4.82 (µv) in Group 2 was reduced compared to 22.68 (µv) in Group 1 in the Light 30 Hz Flicker.
Conclusions :
The ERG Amplitude Changes indicated that the ischemia procedure cased damage of the retinal cells and resulted in the retinal disfunction.
This is a 2021 ARVO Annual Meeting abstract.