Awata S, Nakayama K, Suzuki I, Sugahara K, Kodama H
Department of Nutritional Biochemistry, Faculty of Food Science, Kochi Gakuen College, Japan.
Biochem Mol Biol Int. 1995 May;35(6):1331-8.
Developmental changes in the activities of cystathionine beta-synthase and cystathionine gamma-lyase were measured in six regions of rat brain. On day-1, no differences were observed in the activities of cystathionine beta-synthase and cystathionine gamma-lyase among these regions, the values being about 40 nmol/h/mg protein, and 3 nmol/h/mg protein, respectively. Cystathionine beta-synthase activity increased gradually during development at almost the same rate in each region, reaching the adult level at week-4 (about 4-fold). Cystathionine gamma-lyase activity also increased during development, reaching adult level at week-2. But, the increase of enzyme activity in the cerebellum (about 1.8-fold) was clearly lower than that in the other regions (about 4-fold). Cystathionine gamma-lyase content in the various regions of week-3 rat brain estimated by immunoblotting was consistent with the enzyme activity, and the enzyme level in the cerebellum was lower than that in the other regions. Cystathionine content of cerebellum in week-3 increased rapidly during development, and was about five-fold more than that on day-1. However, cystathionine content in the other regions did not change during development. These findings indicated that at least one reason of the high content of cystathionine in the 3 weeks rat cerebellum was due to the low level of cystathionine gamma-lyase.
测定了大鼠脑六个区域中胱硫醚β-合酶和胱硫醚γ-裂解酶活性的发育变化。在出生第1天，这些区域中胱硫醚β-合酶和胱硫醚γ-裂解酶的活性未观察到差异，其值分别约为40 nmol/h/mg蛋白质和3 nmol/h/mg蛋白质。胱硫醚β-合酶活性在发育过程中以几乎相同的速率在每个区域逐渐增加，在第4周达到成年水平（约4倍）。胱硫醚γ-裂解酶活性在发育过程中也增加，在第2周达到成年水平。但是，小脑中小酶活性的增加（约1.8倍）明显低于其他区域（约4倍）。通过免疫印迹估计的第3周大鼠脑各区域中胱硫醚γ-裂解酶含量与酶活性一致，且小脑中的酶水平低于其他区域。第3周小脑中胱硫醚含量在发育过程中迅速增加，约为出生第1天的五倍。然而，其他区域中的胱硫醚含量在发育过程中没有变化。这些发现表明，3周龄大鼠小脑中胱硫醚含量高的至少一个原因是胱硫醚γ-裂解酶水平低。
