塩酸ブレオマイシンの褥瘡発生に及ぼす影響に関するウサギを用いた病理学的研究

Pathologic Study of the Effects of Bleomycin on Development of Pressure Ulcers in Rabbits

要旨

　抗がん剤である塩酸ブレオマイシン（BLM）の褥瘡発生に及ぼす影響について，実験動物を用い病理学的手法により検索した．本研究では，10匹のウサギをBLM投与群と非投与群（対照群）の2群に分け実験を行った．すなわち，BLMを2.5mg/kgの量で週1回，5週間筋肉内投与したウサギをBLM投与群とし，BLMの溶媒である生理食塩液を同様に投与したウサギを対照群とした．これらの各群の動物に作製した褥瘡について，肉眼的観察と組織学的検査を実施し，褥瘡発生に及ぼすBLMの影響について検討した．実験的褥瘡は，ウサギの腰背部皮膚を除毛した後，大腿骨第三転子部上の組織に138kPa（1.4kg/cm2）の圧力で4時間加圧することにより作製した．病巣の肉眼的観察は，作製後5日目まで毎日実施し，組織学的検査は，5日目の褥瘡および肺について光学顕微鏡を用いて実施した．その結果，肉眼的観察では，BLM投与群において，作製後1日目に強い発赤と浮腫形成が観察され，褥瘡治癒遅延も認められた．組織学的検査では，全ての動物に肺病変は観察されなかった．褥瘡の組織所見では，BLM投与群において，多発性血栓形成や表皮再生不良が認められた．

Abstract

　We investigated experimentally the effects of bleomycin hydrochloride (BLM), an antineoplastic agent, on the development of pressure ulcers in rabbits. The animals were divided into two groups. Group 1 comprised 5 treated rabbits that were administered a dose of 2.5mg/kg BLM intramuscularly once a week for 5 weeks. Group 2 comprised 5 control rabbits that were administered saline intramuscularly once a week for 5 weeks. Both macroscopic and histologic studies of the ulcers were performed. We produced pressure ulcers in the rabbits by exposing their skin over the trochanter to a pressure of 138kPa (1.4kg/cm2) for 4 h. The ulcers were studied macroscopically for 5 days after the application of pressure. A histologic study was also performed on the ulcers at 5 days, as well as on the lungs of all rabbits.

　Macroscopic observation revealed severe edema at the compression site in the rabbits treated with BLM one day after release of pressure, and the healing of the pressure ulcers was also retarded in these rabbits in comparison with the ulcers in the control group. There were no histologic lesions in the lungs of any rabbits. Histologic study of the pressure ulcers revealed formation of multiple thromboses and a low level of epidermal cell proliferation in the animals treated with BLM.