Dose-modifying factor for captopril for mitigation of radiation injury to normal lung. J Radiat Res 2012 Jul;53(4):633-40
Date
07/31/2012Pubmed ID
22843631Pubmed Central ID
PMC3393339DOI
10.1093/jrr/rrs004Scopus ID
2-s2.0-84872114086 (requires institutional sign-in at Scopus site) 40 CitationsAbstract
Our goal is to develop countermeasures for pulmonary injury following unpredictable events such as radiological terrorism or nuclear accidents. We have previously demonstrated that captopril, an angiotensin converting enzyme (ACE) inhibitor, is more effective than losartan, an angiotensin type-1 receptor blocker, in mitigating radiation-pneumopathy in a relevant rodent model. In the current study we determined the dose modifying factors (DMFs) of captopril for mitigation of parameters of radiation pneumonitis. We used a whole animal model, irradiating 9-10-week-old female rats derived from a Wistar strain (WAG/RijCmcr) with a single dose of irradiation to the thorax of 11, 12, 13, 14 or 15 Gy. Our study develops methodology to measure DMFs for morbidity (survival) as well as physiological endpoints such as lung function, taking into account attrition due to lethal radiation-induced pneumonitis. Captopril delivered in drinking water (140-180 mg/m(2)/day, comparable with that given clinically) and started one week after irradiation has a DMF of 1.07-1.17 for morbidity up to 80 days (survival) and 1.21-1.35 for tachypnea at 42 days (at the peak of pneumonitis) after a single dose of ionizing radiation (X-rays). These encouraging results advance our goals, since DMF measurements are essential for drug labeling and comparison with other mitigators.
Author List
Medhora M, Gao F, Fish BL, Jacobs ER, Moulder JE, Szabo AAuthor
Aniko Szabo PhD Professor in the Institute for Health and Equity department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Angiotensin-Converting Enzyme InhibitorsAnimals
Captopril
Dose-Response Relationship, Radiation
Female
Humans
Lung
Lung Injury
Proportional Hazards Models
Radiation Injuries
Radiation Pneumonitis
Rats
Rats, Wistar
Respiration
Tachypnea
Time Factors