锰对仔鼠脑尾壳核与黑质谷氨酸脱羧酶的影响

Effects of manganese on activity of GAD in caudate putamen nucleus and substantia negra of filial rats

目的研究大鼠染锰后对其仔鼠脑尾壳核、黑质谷氨酸脱羧酶(GAD)活性的影响。方法将妊娠大鼠随机分为对照组(A组)和染锰组(B、C组),B、C2组染锰剂量分别为38,78mol/L,腹腔注射氯化锰,隔日一次,共8次。待其自然分娩后,取21日龄仔鼠脑组织冰冻切片,用免疫组织化学链霉抗生物素-生物素法(S-P法染色),检测仔鼠脑尾壳核、黑质GAD活性。结果21日龄仔鼠脑黑质、尾壳核GAD活性C组和A组之间比较,差异有统计学意义(P<0.01),B组和A组,B组和C组之间比较差异,有统计学意义(0.01<P<0.05)。结论孕期染锰可引起仔鼠脑尾壳核、黑质GAD活性升高,引起谷氨酸(Glu)含量下降,γ氨基丁酸(GABA)含量升高,Glu/GABA比值降低,引起学习记忆能力下降。

Objective To study the effects of manganese on the activity of glutamic acid decarboxylase（GAD） in the caudate putamen nucleus and substantia negra of filial rats in the pregnant rats exposed to manganese. Methods Pregnant rats were randomly divided into three groups, including group A, group B and group C, group A was used as control group, group B and group C received intraperitoneal injections of manganese chloride （MnCl2） 38 mol/kg, 78 mol/kg respectivly for 8 times every two days. After normal delivery , the activity GAD in the caudate putamen nucleus and Substantia Negra of 21-day-old filial rata＇brains were determined with peroxidase conjugated method. Results The activity of GAD in the Caudate putamen nucleus and Substantia Negraof 21-day-old rats of group C was increased significantly compared with group A （ P〈0.01 ） and group B（0.01 〈 P〈 0.05）, and that of group A was decreased significantly compared with group B （0.01〈P〈0.05 ）. Conclusion The activity of GAD in caudate putamen nucleus and substantia Negra of brains of filial rat could be promoted after the pregnant rats exposed to MnCl2, so that the level of Glu was decreased and level of GABA was increased in this area, and the ratio of Glu/GABA was decreased, thus filial rats＇s remembrance was weaken.