Martínez Villayandre Beatriz, Paniagua Miguel Angel, Fernández-López Arsenio, Chinchetru Miguel Angel, Calvo Pedro
Dpto. Bioquímica y Biología Molecular, Facultad de Veterinaria, Universidad de León, 24007 León, Spain.
Brain Res. 2004 Dec 3;1028(2):148-55. doi: 10.1016/j.brainres.2004.09.008.
A comparative study using membrane homogenate binding, autoradiography, and Western blot assays was carried out to determine the age-related changes in N-methyl-D-aspartate (NMDA) receptors in 4-, 12- and 24-month-old male Wistar rats, treated or not with vitamin E. Vitamin E treatment was 20 mg/kg i.p. daily for 15 days. [(3)H] 5-methyl-10,11-dihydro-5H-dibenzo (a,d) cycloheptan-5,10-imine maleate (MK-801) binding was significantly increased in all areas studied (cortex and hippocampus) at all ages when rats received this treatment. A Western blot study in vitamin-E-treated rats and their controls did not reveal significant differences in the amounts of NR2A, an NMDA receptor subunit widely distributed in the brain mainly in cortex and hippocampus. We conclude that the effect of vitamin E on NMDA receptors is largely age independent. Previous reports and our data have described the presence of age-dependent NMDA receptor changes. The effect of vitamin E in aging is considered to be mediated by free radical scavenging, but from our data, we conclude that this mechanism is not relevant for age-dependent NMDA receptor changes. Our results also support that age or vitamin E treatment have no relevant effects on NR2A subunit, at least until 24 months in rats.
采用膜匀浆结合、放射自显影和蛋白质免疫印迹分析进行了一项比较研究，以确定4个月、12个月和24个月大的雄性Wistar大鼠（无论是否接受维生素E治疗）中N-甲基-D-天冬氨酸（NMDA）受体的年龄相关变化。维生素E治疗为每天腹腔注射20mg/kg，持续15天。当大鼠接受该治疗时，在所有研究区域（皮层和海马体），所有年龄段的[(3)H]5-甲基-10,11-二氢-5H-二苯并(a,d)环庚烯-5,10-亚胺马来酸盐（MK-801）结合均显著增加。对接受维生素E治疗的大鼠及其对照组进行的蛋白质免疫印迹研究未发现NR2A（一种主要分布于大脑皮层和海马体的NMDA受体亚基）的量有显著差异。我们得出结论，维生素E对NMDA受体的影响在很大程度上与年龄无关。先前的报道和我们的数据都描述了NMDA受体存在年龄依赖性变化。维生素E在衰老过程中的作用被认为是通过清除自由基介导的，但从我们的数据来看，我们得出结论，这种机制与年龄依赖性NMDA受体变化无关。我们的结果还支持，年龄或维生素E治疗对NR2A亚基没有显著影响，至少在大鼠24个月龄之前是这样。
