摘要: 目的 研究胍丁胺和尼莫地平对锰引起的大鼠脑纹状体谷氨酰胺合成酶、磷酸激活的谷氨酰胺酶和脑皮质Na⁺-K⁺-ATP酶、Ca²⁺-ATP酶活性变化的影响。 方法 32只大鼠按体重随机分成4组,第1组为对照组;第2组为单纯染锰组,第3,4组分别为胍丁胺和尼莫地平预处理干预组,连续干预并染锰4周。最后1次染毒后24h,将每组大鼠直接处死,断头取脑,在冰浴下分离脑纹状体和皮质,应用比色法测定脑纹状体中谷氨酰胺合成酶、磷酸激活的谷氨酰胺酶和脑皮质中Na⁺-K⁺-ATP酶和Ca²⁺-ATP酶的活性。 结果 在单纯染200μmol/kg的氯化锰组中,谷氨酰胺合成酶〔(50.41±5.47)U/(min·g·pro)〕、Na⁺-K⁺-ATP酶(2.13±0.15)μmol/(h·mg)、Ca²⁺-ATP酶(0.56±0.28)μmol/(h·mg),3种酶与对照组比较活性明显降低(P＜0.01),磷酸激活的谷氨酰胺酶(72.24±9.38)μmol/(min·g·pro),与对照组比较活性明显升高(P＜0.01);而21.9μmol/kg的胍丁胺和2.4 mmol/kg的尼莫地平预处理干预组与单纯染锰组比较,谷氨酰胺合成酶、Na⁺-K⁺-ATP酶、Ca²⁺-ATP酶活性明显升高(P＜0.01),磷酸激活的谷氨酰胺酶活性明显降低(P＜0.01)。 结论 胍丁胺和尼莫地平对锰致大鼠兴奋性毒性有一定的保护作用。

Abstract: Objective To determine whether ag matine and nimodipine can prevent the toxic effects of manganese on glu-tamine synthetase,phosphate activated glutaminase,Na⁺-K⁺-ATPase and Ca²⁺-ATPase in rat striatum. Methods 32 Wistar rats were divided into four groups by weight at randomization.The first group was the control group,the second group was given MnCl₂ only.The third and fourth groups were given agmatine and nimodipine respectively.The administration lasted 4 weeks.24 hours after the lastinjection,the activities of glutamine synthetase and phosphate activ ated glutaminase in striatum,the activities of Na⁺-K⁺-ATPase and Ca²⁺-ATPase in pallium were determined. Results Compared with the control group,the activities of glutamine synthetase [(50.41±5.47)U/(min·g·pro)],Na⁺-K⁺-ATPase [(2.13±0.15)Lmol/(h·mg)]and Ca²⁺-ATPase [(0.56±0.28)Lmol/(h·mg)] in the second g roup decreased significantly(P＜0.01).The activity of phosphate activated glutaminase [(72.24±9.38)Lmol/min·g·pro)]increased significantly(P＜0.01).Compared with the second group,the activities of glutamine snthetase,Na⁺-K⁺-ATPase and Ca²⁺-ATPase in the third and fourth groups increased significantly(P＜0.01).And the activity of phosphate activated glutaminase decreased significantly(P＜0.01). Conclusion Agmatine and nimodipine have certain protective effects on the excitotoxicity induced by manganese in Wistar rats.