Menkes病マウス脳のモノアミン・オキシダーゼ活性レベルの組織化学的および生化学的検討

Histochemical and Biochemical Investigations of Monoamine Oxidase Activity Level in the Brain of the Brindled Mouse

　Menkes病における脳幹障害の程度を知るために脳のモノアミン・オキシダーゼ（MAO）含有ニューロンの形態とその酵素活性をみておくことは大切である。これを行う目的で，モデル動物brindled mouse（BM）とその正常対照の脳のMAO活性レベルを組織化学的方法（Araiらの共役過酸化法）と生化学的方法（Kramlのキヌラミンを基質とする蛍光法）を用いて検討した。その結果，MAO活性陽性ニューロン群の染色性とその脳内分布は正常対照とBMとの間で，明らかな差は認められなかった。また生後3-12日齢のマウス脳のMAO活性レベルは，正常マウスでもBMでも，日齢の増加に伴い共に上昇すること，同じ日齢では両者の間に有意差が認められないことが明らかになった。この結果から，マウスMenkes病においては，MAO含有ニューロンは有意に侵されないこと，従って脳幹・間脳の障害がもしあるとしてもMAO含有ニューロンに影響を与えるような障害ではないことがわかった。

In order to make clear the degree of brainstem affection in Menkes disease, it is important to inves-tigate morphological and enzymatic changes of monoamine oxidase (MAO) -containing neurons in the brain in this disease.

For this purpose, MAO activity levels in brain tissue from normal and brindled mice were examined histochemically and biochemically. A coupled peroxidatic oxidation method for the histo-chemistry and a rapid microfluorimetric method for the biochemical assay were adopted. Animals aged 3 days, 8 days, 13 days, 3 months and 12 months were used for the histochemical study. Three-, 7-, and 12-day-old mice were used for the biochemical study. Histochemical examinations showed no significant differences in the stainability, morphol-ogy and distriution of MAO positive neurons in thebrain between normal and brindled mice at the same age. Biochemical assays revealed that MAO activ-ity levels in the brain of the postnatal brindled mice rose with age as highly as those in the normal control mice. Threre were no significant differences in them between normal and brindled mice at the same age. The results indicate that in Menkes disease in mice the brainstem affection, if there is, is not so severe as to influence the morphology and enzyme activity of MAO-containing neurons.