^Ga、^Inは悪性腫瘍組織の周辺部の炎症部位に大量に集積するが、^Tl、^K、^Rb、^Csは悪性腫瘍組織内の腫瘍細胞の生育部へ集積し、壊死部および炎症部への集積はほとんどなかった。これとは逆に同じアルカリ金属でも^Naは壊死部に集積し、腫瘍細胞の生育部には集積しなかった。一方、^Tm、^Ybは炎症部にかなり多量に集積したが、^Ga、^Inとはやや異なった集積を示した。一方、^Sc、^Cr、^Zr、^Nb、^Hf、^Taは悪性腫瘍組織の炎症部への集積が極めて高く、腫瘍細胞の生育部および壊死部への集積は非常に少なかった。^Zn、^Pdは腫瘍細胞の生育部に多く集積し、壊死部および炎症部への集積はほとんど認められなかった。悪性腫瘍組織への^Na、^Rb、^Csおよび^Tlの集積に関しては、イオン半径が0.133nmを超え、組織中でイオンとして存在する1価の陽イオンは、生体内でカリウムイオンと類似の挙動をする。カリウムとカリウム類似元素(Tl、Rb、Cs)はNa^+,K^+一ATPase活性が高い生きた腫瘍細胞へ大量に取り込まれる。ナトリウムイオンは主に細胞外液中に存在するために、腫瘍細胞の生育部には集積せず、壊死部に集積すると考えられた。 ^Gaは炎症巣へも多量に集積するので、^Gaの炎症巣への集積を調べたところ、^Gaは炎症巣の辺縁部に密集しており、好中球およびマクロファージが混在して浸潤した皮下組織に^Gaの強い集積を認めた。この皮下組織で^Gaは主に細胞間隙に存在していた。また炎症巣では血管透過性が非常に大きいことがわかった。これらのことから、^Gaは炎症巣で透過性の亢進した血管から膿瘍の外側の好中球およびマクロファージが混在して浸潤した皮下組織へ多量に漏洩し、そこで細胞間隙に存在する酸性ムコ多糖に結合していると推定された。 The purpose of this study is to observe thedistribution of the radioactive metal elements in malignant tumor tissue by autoradiography and to invesigate the relationship between the accumulation in tumor tissue and properties of these metal elements. In addition, this study is undertaken to investigate the mechanism of accumulation of ^ Ga in the inflammatory lesion. In Ehrlich tumor and Yoshida sarcoma which had been administered with ^Ga-citrate and ^In-citrate, respectively, the concentrations of these nuclides were predominant in inflammatory tissues rather than in viable tumor tissue, and were not seem in necrotic tumor tissue. In the case of Ehrlich tumor and Yoshida sarcoma administered with ^Tl-chloride, ^Rb-chloride and ^Cs-chloride, respectively, a large amount of these nuclides was accumulated in viable tumor tissue, andonly small amounts were accumulated in connective tissue, regardless of the time after administration, and were not seen in necrotic tumor tissue. In the case of tumors injucted with ^Na-chloride, the concentration of ^Na was more dominant in necrotic tumor tissue than in viable tumor tisue and connective tissue, regardless of the time after injuctions.. From data of our experiments, mechanisms of ^Ga uptake into inflammatory lesion were concluded as follows : accumulation of _Ga in the inflammatory lesion is primarily due to leakage of _Ga into the subcutaneo tissue infiltrated with neutrophils and macrophages through capillaries with increased permeability. In the inflammatory lesion, _Ga is preferentially bound to the acid mucopolysaccharides which compose intercellular substances.The purpose of this study is to observe thedistribution of the radioactive metal elements in malignant tumor tissue by autoradiography and to invesigate the relationship between the accumulation in tumor tissue and properties of these metal elements. In addition, this study is undertaken to investigate the mechanism of accumulation of ^ Ga in the inflammatory lesion. In Ehrlich tumor and Yoshida sarcoma which had been administered with ^Ga-citrate and ^In-citrate, respectively, the concentrations of these nuclides were predominant in inflammatory tissues rather than in viable tumor tissue, and were not seem in necrotic tumor tissue.In the case of Ehrlich tumor and Yoshida sarcoma administered with ^Tl-chloride, ^Rb-chloride and ^Cs-chloride, respectively, a large amount of these nuclides was accumulated in viable tumor tissue, andonly small amounts were accumulated in connective tissue, regardless of the time after administration, and were not seen in necrotic tumor tissue. In the case of tumors injucted with ^Na-chloride, the concentration of ^Na was more dominant in necrotic tumor tissue than in viable tumor tisue and connective tissue, regardless of the time after injuctions..From data of our experiments, mechanisms of ^Ga uptake into inflammatory lesion were concluded as follows : accumulation of _Ga in the inflammatory lesion is primarily due to leakage of _Ga into the subcutaneo tissue infiltrated with neutrophils and macrophages through capillaries with increased permeability. In the inflammatory lesion, _Ga is preferentially bound to the acid mucopolysaccharides which compose intercellular substances.研究課題/領域番号:04670663, 研究期間(年度):1992–1993出典:「オートラジオグラフィによる放射性金属元素の悪性腫瘍組織内分布の研究と臨床応用」研究成果報告書 課題番号04670663(KAKEN:科学研究費助成事業データベース(国立情報学研究所)) 本文データは著者版報告書より作