Radiation Oncology Journal
- 제19권3호
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- Pages.265-274
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- 2001
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- 2234-1900(pISSN)
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- 2234-3156(eISSN)
백서모델에서 방사선 직장염 유발인자로서의 Nitric oxide의 역할
Radiation-Induced Proctitis in Rat and Role of Nitric Oxide
-
전미선
(아주대학교 의과대학 치료방사선과학교실) ;
-
강승희
(아주대학교 의과대학 치료방사선과학교실) ;
- 진윤미 (국민건강보험공단 일산병원 해부병리학과) ;
-
오영택
(아주대학교 의과대학 치료방사선과학교실) ;
- 길훈종 (아주대학교 의과대학 치료방사선과학교실) ;
- 오태영 (동아제약연구소) ;
-
안병옥
(동아제약연구소)
-
Chun Mison
(Department of Radiation Oncology, School of Medicine, Ajou University) ;
-
Kang Seunghee
(Department of Radiation Oncology, School of Medicine, Ajou University) ;
- Jin Yoon-Mi (Department of Anatomic Pathology, National Health Insurance Corporation Ilsan Hospital) ;
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Oh Young-Taek
(Department of Radiation Oncology, School of Medicine, Ajou University) ;
- Kil Hoon-Jong (Department of Radiation Oncology, School of Medicine, Ajou University) ;
- Oh Tae-Young (Research Laboratories, Dong-A Pharm. Co. Ltd.) ;
-
Ahn Byoung-Ok
(Research Laboratories, Dong-A Pharm. Co. Ltd.)
- 발행 : 2001.09.01
초록
목적 : 방사선 직장염은 골반부위에 방사선치료를 받는 환자에서 나타나는 급성부작용 중의 하나이다. 이러한 방사선 직장염은 병리학적으로 염증성 대장질환과 유사한 소견을 보인다. 따라서 염증성 대장질환의 유발인자로서 최근 활발하게 연구되고 있는 nitric oxide (NO)의 과다생성이 방사선 직장염을 유발하는 주요 원인일 수도 있다. 이를 검증하기 위하여 본 연구자들은 적절한 방사선 직장염 동물모델을 확립하고 이 모델에서 NO의 과다생성과 직장점막의 손상 정도의 상호 관련성을 연구하였다. 대상 및 방법 : 암컷 백서(Wistar)의 직장에
Purpose : Proctitis is one of acute complications encountered when radiotherapy was appled to the pelvis. Radiation-induced proctitis represents similar microscopic findings that are observed in inflammatory bowel disease (IBD). Nitric oxide (NO) plays an important role in the inflammatory process and many data suggest a close relationship between NO production and gastrointestinal inflammation. This study was aimed to establish the optimal radiation dose for radiation-induced proctitis in rat and to find a relationship between radiation proctitis and NO production. Materials and methods : Female Wistar rats, weighing from 150 to 220 g, received various doses(10-30 Gy) of radiation to the rectum. On the 5th and 10th day after irradiation, rectal specimens were evaluated grossly and microscopically. In addition, the degree of NO production by irradiation dose was evaluated by study with NOS expression and nitrite production in the irradiated rectal tissue. To evaluate relationship between radiation proctitis and NO, we administered aminoguanidine, iNOS inhibitor and L-arginine, substrate of NOS to rats from 2 days before to 7 days after the irradiation. Results : There were obvious gross and hostological changes after 17.5 Gy or higher radiation dose but not with 15 Gy or less radiation dose. Twenty Gy or higher dose of radiation caused Grade 4 damage in most of rectal specimens which were more likely to be related to the late complications such as fibrosis, rectal bleeding and rectal obstruction. A single fraction of 17.5 Gy to the rat rectum is considered to be an optimal dose to produce commonly experienced proctitis in the clinic. The result demonstrated that severity of microscopic damage of rectal mucosa from irradiation significantly correlated with iNOS over-expression. However, administration of iNOS inhibitor or substrate of iNOS did not influence the degree of rectal damage. Conclusion : A single fraction of 17.5 Gy irradiation to the rat rectum considered to be an optimal dose for radiation induced proctitis model. These results indicated that an excess production of NO contributes to pathogenesis of radiation-induced proctitis in part but was not the direct cause of rectal damage.