Katoh H, Kawana A, Shioya S, Tsuji C, Ohta Y
Department of Internal Medicine, School of Medicine, Tokai University, Kanagawa, Japan.
Nihon Kyobu Shikkan Gakkai Zasshi. 1996 Mar;34(3):275-80.
A common side effect of radiotherapy is the development of fibrosis in the irradiated tissue. To study the effects of methylprednisolone on acute radiation-induced lung injury, we counted neutrophils, lymphocytes, and macrophages, and measured the expression on alveolar macrophages of lymphocyte function associated molecule-1 (LFA-1) in bronchoalveolar lavage fluid recovered from irradiated rat lungs. Twenty 10-week-old male Wistar rats were divided into 4 groups of 5 rats each: (1) a radiation group (R), which received 20 Gy of radiation from 60Co to the left hemithorax in one fraction; (/) a methylprednisolone treatment group (RS), which received the same dose of radiation as the R group, along with 2.0 mg x kg-1 of methylprednisolone (6 alpha methylprednisolone 21-acetate) by intramuscular injection 6 hours before and every 48 hours after irradiation; (3) an untreated control group (C); and (4) a methylprednisolone control group (S), which received the same dosage of methylprednisolone as the RS group. Rats were kept under specific-pathogen-free conditions. Bronchoalveolar lavage of the left lung was done in all 4 groups 2 week after irradiation. The number of neutrophils in the recovered fluid was significantly higher in the R and RS groups than in the C and S groups. The expression of LFA-1 on alveolar macrophages was significantly higher in the R group than in the RS, C, and S groups. The number of neutrophils in bronchoalveolar lavage fluid and the expression of LFA-1 on alveolar macrophages were significantly higher in the R group than in the RS groups. These results suggest that the increase in the expression of LFA-1 on alveolar macrophages and the increase in the number of neutrophils in bronchoalveolar lavage fluid are related to acute radiation-induced lung injury. Methylprednisolone suppressed the expression of LFA-1 on alveolar macrophages and the increase in the number of neutrophils measured in bronchoalveolar lavage fluid 2 weeks after irradiation.
放射治疗的一个常见副作用是在受照射组织中发生纤维化。为了研究甲基强的松龙对急性放射性肺损伤的影响，我们对中性粒细胞、淋巴细胞和巨噬细胞进行了计数，并测量了从受照射大鼠肺中回收的支气管肺泡灌洗液中肺泡巨噬细胞上淋巴细胞功能相关分子-1（LFA-1）的表达。20只10周龄雄性Wistar大鼠被分为4组，每组5只：（1）放射组（R），接受单次60Co对左半胸20 Gy的照射；（2）甲基强的松龙治疗组（RS），接受与R组相同剂量的照射，并在照射前6小时及照射后每48小时通过肌肉注射2.0 mg/kg-1的甲基强的松龙（6α-甲基强的松龙21-乙酸酯）；（3）未治疗对照组（C）；（4）甲基强的松龙对照组（S），接受与RS组相同剂量的甲基强的松龙。大鼠饲养在无特定病原体条件下。照射后2周对所有4组大鼠的左肺进行支气管肺泡灌洗。回收液中中性粒细胞的数量在R组和RS组显著高于C组和S组。R组肺泡巨噬细胞上LFA-1的表达显著高于RS组、C组和S组。支气管肺泡灌洗液中中性粒细胞的数量以及R组肺泡巨噬细胞上LFA-1的表达显著高于RS组。这些结果表明，肺泡巨噬细胞上LFA-1表达的增加以及支气管肺泡灌洗液中中性粒细胞数量的增加与急性放射性肺损伤有关。甲基强的松龙抑制了照射后2周肺泡巨噬细胞上LFA-1的表达以及支气管肺泡灌洗液中中性粒细胞数量的增加。
