Monecular aspect of cholesterol metabolism in gallstone formation

1. 人胆固醇- 7 -羟化酶测定当我们将微粒体溶解并理想地重建P450反应体系后进行测定时，不测定微粒体胆固醇- 7 -羟化酶活性；而线粒体胆固醇27-羟化酶活性则在溶解线粒体并理想地重构P450反应体系后显著增加。结果将予以公布。胆固醇和维生素D_3代谢胆固醇27-羟化酶和维生素D_3 25-羟化酶由一种共同的酶完成。为了调查这些现象，我着重研究了与维生素D_3有关的酶。首先，我们从大鼠肾脏线粒体中纯化25-羟基维生素d_31 α -羟化酶，并分两篇论文发表。该酶的底物特异性有待进一步研究。

1. Assay of human cholesterol 7alpha-hydroxylaseMicrosomal cholesterol 7alpha-hydroxylase activity was not assayed as an increased measurement when we measured it after solubilizing the microsomes and reconstituting the P450 reaction system ideally ; whereas mitochondrial cholesterol 27-hydroxylase activity was assayed as a markedly increased measurement when we measured it after solubilizing the mitochondria and reconstituting the P450 reaction system ideally.The results will be published.2. Cholesterol and vitamin D_3 metabolismsCholesterol 27-hydroxylase and vitamin D_3 25-hydroxylase are performed by one common enzyme.To survey these phenomena, I focused to study enzymes concerning vitamin D_3. First, we purified 25-hydroxyvitamin D_3 1alpha-hydroxylase from rat kidney mitochondria, and published as two papers.Substrate specificity of the enzyme will be studied in future.