Johnson P I, Blusztajn J K
Department of Pathology and Laboratory Medicine, Boston University School of Medicine, MA 02118, USA.
Neurochem Res. 1998 May;23(5):583-7. doi: 10.1023/a:1022470301550.
Phosphatidylethanolamine N-methyltransferase (PEMT) activity was measured by a radioenzymatic assay in homogenates of brain and liver obtained from Sprague Dawley rats fed a choline-free or control (0.3 g/kg of choline chloride) diet for seven days. Choline deficiency increased PEMT activity in the liver of male rats by 34% but had no effect on hepatic PEMT in females. In contrast, brain PEMT activity was increased in brain of choline deficient females (by 49%) but was unaltered in males. Activation of the PE methylation pathway in female brain may constitute a compensatory mechanism to sustain PC synthesis during choline deficiency.
通过放射性酶法测定了从喂食无胆碱或对照（0.3 g/kg氯化胆碱）饮食7天的斯普拉格-道利大鼠获得的脑和肝匀浆中磷脂酰乙醇胺N-甲基转移酶（PEMT）的活性。胆碱缺乏使雄性大鼠肝脏中的PEMT活性增加了34%，但对雌性大鼠肝脏中的PEMT没有影响。相反，胆碱缺乏的雌性大鼠大脑中的PEMT活性增加（增加了49%），而雄性大鼠大脑中的PEMT活性没有改变。雌性大脑中PE甲基化途径的激活可能构成一种补偿机制，以在胆碱缺乏期间维持PC的合成。
