Simultaneous determination of biobehavior of Sc, Mn, Fe, Co, Zn, Se, Rb, Y, and Zr in mice bred under different O2 gas percentage circumstance

Abstract

A no-carrier-added multitracer solution was obtained from a pure Ag target irradiated by heavy-ion beam. Ten radioisotopes were produced by bombardment in a cyclotron. One month later, an animal experiment was started using those radioisotopes. Physiological saline solutions containing the radioactive multitracer were intraperitoneally injected into mice. The injected mice were housed in steel net cases, into which gas was supplied at a constant velocity from cylinders. In this manner, those mice were bred in atmospheres containing O2 gas in four different percentages (10, 20, 80 and 100 percent). At 48 hours after injection of the multitracer, the mice were sacrificed under ether anesthesia and their blood was collected. Then, nine types of tissues including brain, cardiac muscle and lung and their blood samples were freeze-dried. The dried samples were subjected to gamma-ray spectrometry to examine the tissue uptake rate of each tracer. Although all the liver uptake rates except that of Rb were found to be equal within the standard deviations under the four different atmospheres, the uptake rate of Rb tracer in 10 percent O2 atmosphere was higher than that under the other atmospheres. The uptake rates of Se and Rb tracers in all tissues and blood samples were compared. It was found that the Rb uptake rates in all soft tissues and blood samples in 10 percent O2 gas atmosphere were higher than those under the other three circumstances.

純Agターゲットに重イオンビームを照射して、担体非添加マルチトレーサ溶液を得た。サイクロトロン衝撃を加えて10種の放射性同位体を生成し、1カ月後に動物実験を行った。放射性マルチトレーサを含む生理的食塩溶液をマウスに腹腔内注射した。注射したマウスを鋼鉄製ケージ内に入れ、シリンダから一定気体流を流した。このようにして、4つの異なるO2気体百分率環境(10、20、80および100%)でマウスを飼育した。マルチトレーサを注入後48時間してマウスをエーテル麻酔し、血液を採取した。その後、脳、心筋、肺など9組織と血液を凍結乾燥し、γ線分光分析を行い、マルチトレーサの組織取込率を調べた。肝臓の取込率については、Rbを除くと4環境下において標準偏差内で等しかったが、Rbトレーサ取込率は10%O2環境下において他の環境下より高かった。すべての組織と血液におけるSeおよびRbトレーサの取込率を比較した。10%O2環境下における軟組織と血液のRb取込率は、他の3環境下におけるより高かった。