약물로 유도된 망막변성 흰 쥐에서 발생한 망막전위도의 초기 가역적 변화

• 영문명: Early Reversible Changes on ERG in Pharmaceutically Induced Retinal Degeneration in Rats
• 발행기관: 대한안과학회
• 저자명: 노규화 박태관 온영훈,Kyu Hwa Roh, M.D., Tae Kwann Park, M.D., Young Hoon Ohn, M.D., Ph.D.
• 간행물 정보: 『대한안과학회지』Ophthalmological Society,volume47,number7, 1117~1125쪽, 전체 9쪽
• 주제분류: 의약학 > 기타의약학
• 파일형태: PDF
• 발행일자: 2006.07.31

영문 초록

Purpose: To evaluate the early ERG (electroretinogram) changes in N-methyl-N-nitrosourea (MNU)-induced retinal degeneration in rats. Methods: Thirty-six 6-week-old male rats were injected intraperitoneally with 60mg/kg MNU and divided into 6 groups. Histology and ERG were recorded for the rats of each group before treatment and at 3, 6, 12, 18, and 24 hours after MNU injection. Promptly after the ERG recording, rats were sacrificed and the eyeballs prepared for histologic sectioning. The Tdt-mediated dUTP-digoxigenin nick end labeling (TUNEL) method was used to detect photoreceptor cell death. Results: The first decreases of ERG responses were noticed maximally at 3 hours after the treatment. Thereafter, the amplitude of the responses was partially recovered at 12 hours post-treatment. The second decrease of ERG amplitudes was observed in the 18-hour recordings, and those changes progressed to 24 hours after the treatment. In the histologic findings, TUNEL (+) cells in the Outer Nuclear Layer (ONL) were not detected at 3 hours after MNU injection, but were initially noticed at 6 hours post-injection. Conclusions: The first decreases of ERG amplitudes proceeded the appearance of TUNEL (+) cells in ONL, and these electrophysiological changes seemed to not be related to photoreceptor cell death. We propose that electrophysiological changes observed might be related to the MNU-induced activity enhancement of guanylate cyclase in the phototransduction pathway. We also show that photoreceptor cell death in the MNU-induced retinal degeneration model occurs at 6 hours after the treatment, which is earlier than the results of previous reports.

키워드

Key Words: Electroretinogram, Guanylate cyclase, MNU, Phototransduction, TUNEL