Comparative distribution of the trace elements Sc, Mn, Fe, Co, Zn, Se, Rb, and Zr in the brain and other organs of C57BL/6N mice

Abstract

Multitracer technique has been applied to the study of biobehavior of Sc, Mn, Fe, Co, Zn, Se, Rb and Zr trace elements in normal C57BL/6N mice. The tissue distribution of the eight elements was examined among 11 organs and blood, and evaluated in terms of tissue uptake rate. Preparation process of no-carrier-added radioactive multitracer solution for injection use was described. Procedures for the intraperitoneal injection of the solution into the mice and for the measurement of blood and tissue samples were presented. Tissue uptake rates of trace elements have been measured. All the eight radioactive tracers were observed in the cardiac muscle, lung, liver, spleen, pancreas and kidneys. As far as the uptake rate of Fe is concerned, it was found to be negligibly low in the brain, muscle and testes, on the contrary, be significantly high in the kidney, liver, pancreas and spleen. It was estimated that the transportation rates of Fe tracer to brain, muscle and testes are considerably slower than those to kidneys, liver, pancreas and spleen due to the difference in the transport mechanism.

C57BL/6N正常マウス体内でのSc、Mn、Fe、Co、Zn、Se、Rb、およびZrの微量元素の生体挙動の研究に多重トレーサ手法を適用した。8元素の生体内分布を11器官および血液を対象に調べ、生体内取込み率で評価した。マウスへの注射用の担体無添加の放射性多重トレーサ溶液の調製法を記述した。マウスへの溶液の腹腔内注射方法および血液と生体組織試料の測定方法を述べた。微量元素の生体内取込み率を測定した。8種の放射性トレーサすべてを心筋、肺、肝臓、ひ臓、すい臓、腎臓で観測した。Feの取込み率に関しては、脳、筋肉、精巣では極めて少なく、反対に腎臓、肝臓、すい臓、ひ臓では著しく高いことが分かった。輸送メカニズムの違いにより腎臓、肝臓、すい臓、ひ臓への輸送速度に比べて、脳、筋肉、精巣へのFeトレーサの輸送速度はかなり遅いと推定した。