缺锌对大鼠海马结构含生长抑素mRNA神经元的影响

EFFECT OF ZINC DEFICIENCY ON SOMATOSTATIN mRNA CONTAINING NEURONS IN THE HIPPOCAMPAL FORMATION OF THE RAT

要采用缺锌饲料喂养动物四周后，用原位杂交组织化学结合图象分析技术，研究了缺锌大鼠海马结构内含生长抑素mR-NA神经元的变化。并采用原子吸收分光光度计测定血浆锌含量。结果与对照组相比.缺锌大鼠血浆锌含量明显降低（P＜0.05），海马和齿状回合生长抑素mRNA的神经元数目明显减少（P＜0.01），胞体的灰度值明显降低（P＜0.01），而胞体的截面积无明显改变。结果提示，缺锌时，海马结构生长抑素mRNA的表达下调，海马结构神经元合成生长抑素的能力降低。这种变化可能是缺锌影响脑的学习记忆功能的重要原因之一。

To understand the effect of zinc deficiency on somatostatin (SS) neurons in the hippocampal formation, the changes of hippocampal SS mRNA containing neurons were observed in zinc deficient rats. Sixteen male Wistar rats were divided into two groups: zinc deficient group (ZD) with lower zinc containing diet (2 μg/g) and the control group on general diet (100 μg/g). After 4 weeks, the number, gray value and sectional area of hippocampal SS mRNA neurons of 8 rats from each group was observed with in situ hybridization histochemistry combined the image qantitative analysis. and the plasma zinc content was measured with atomic absorptive microscopy and spectroscopy. The results were as follows: as compared with control group. the plasma zinc content of ZD rats was obviously decreased (P<0. 05), the numbers and gray values of the SS mRNA neurons in hippocampus and dentate gyms of ZD rats were significantly reduced (P<0. 01 ). there was no difference in the average sectional area and distribution pattern of the hippocampal SS mRNA neurons. These studies suggested that in zinc deficient rat hippocampal SS mRNA neurons have lowered synthesis capacity. The changes might be one of the major reasons of the influence of zinc deficiency on learning and memory.