锝化学研究Ⅶ．~（99）Tc~m－脑显像剂滞留机制的研究

STUDIES OF TECHNETIUM CHEMISTRY Ⅶ.A STUDY ON THE RETENTION MECHANISM OF￣99Tc￣m-BRAIN IMAGINGS

采用量子化学中的ＣＮＤＯ／２法与分子图型学相结合的方法，首次研究了￣９９Ｔｃ￣ｍ－ＰｎＡＯ类及￣９９Ｔｃ￣ｍ－ＢＡＴ类脑显像剂在脑内的滞留。结果表明，这些显像剂在脑内的滞留与其分子轨道的Ｅ＿ＬＵＭＯ与Ｅ＿ＨＯＭＯ能级之差呈正相关，采用这一指标可对￣９９Ｔｃ￣ｍ－脑显像剂受到谷胱甘肽的－ＳＨ进攻导致滞留的机制给予合理的解释。

The retention mechanism of the brain imagings belonging to analogues of ￣99Tc￣m-PnAO and￣99Tc￣M-BAT is studied with the CNDO/ 2 methed of quantum chemistry and molecular gragphicmethed. The results show that the retention of these imagings in the brain is prqportional to the(E_LUMO-E_HOMO)of molecular orbitals of Tc-complexes,Using this index the retention mecha-nism of ￣99Tc￣m-brain imaging attacked by the glutanthione-SH could be illustrated reasonally.The results give some theoretical informations for designing new brain imaging molecules anduseful suggestion in improving and making brain imaging drugs.