BleomycinのマウスGlioma内取り込みとその抗腫瘍性に関する実験的研究

UPTAKE, DISTRIBUTION AND ANTITUMOR ACTIVITY OF BLEOMYCIN IN MOUSE GLIOMA

　Bleomycin （BLM8は，1962年梅沢らにより発見された制癌剤で^1）2），市川らによりはじめて扁平上皮癌に対する著効が認められた^3）4）。梅沢らは投与後のBLMの臓器内分布を調べた結果，BLMは皮膚に高濃度に分布し，また皮膚ではほとんど不活性化されないのを認め，扁平上皮癌に対するBLMの治療効果の根拠とした^5〜8）。

　発生学的には神経系は皮膚と同様外胚葉性であるので，BLMのgliomaなどの脳腫瘍に対する治療効果が期待されたので，20-methylcholanthreneを用いてマウス脳にgliomaを誘発し，BLMのglioma内分布を検索するとともに，皮下移植gliomaを用いてBLMのg1ioma内不活性化を調べ，さらにBLMの皮下移植gliomaの腫瘍増殖に与える影響を観察し，BLMによるglioma治療の可能性を追求した。

The purpose of the present study was to estimatethe posibility of the treatment of glioma with Bleo-mycin (BLM).

The following experiments were carried out :

(1) The uptake and distribution of ¹⁴C-bleomycin A₂ at two hours after intravenous administration in primary glioma induced by 20-methylcholan-threne and organs in a mouse were determined by measuring radioactivity in tissues.

(2) The distribution of ¹⁴C-bleomycin A₂ in subcutaneously transplanted glioma in mice was measured by radioactivity and antibacterial activity by thin layer paper disc method using B. subtilis as test organism and was determined the inactiva-tion ratio of BLM in glioma tissue.

(3) The changes of tumor size and body weight in mice with subcutaneously transplanted glioma following intraperitoneal administrations of BLM at various levels were checked.

The results of these experiments lead to the following conclusions :

(1) There may be a considerably high uptake of BLM by glioma after intravenous administration.

(2) About two thirds of BLM in glioma may remain in so-called active form which shows anti-bacterial activity.

(3) BLM may have significantly inhibitory effect on the growth of glioma.