组织学切片法在三维重建大鼠海马结构中的应用价值

Three dimensional reconstruction of hippocampus structure in rat brain based on histological serial sections

目的探讨组织学切片法在三维重建大鼠海马结构的应用价值。方法采用成年SD大鼠3只,取全脑至脊髓颈1节段后固定,其中2只标本在冰冻切片机上行冠状面连续冰冻切片,1只标本行正中矢状切片,片厚30μm。所得切片行尼氏染色,在5倍物镜下行显微拍摄。每张切片拍摄4至5张照片,在Photoshop 7.0软件中进行图像拼接,三轴法对所得图片进行配准。根据大鼠脑立体定位图谱在3D-DOCTOR 4.0软件中将连续图像中海马划分为CA1、CA2、CA3和DG 4区,对这4区以及侧脑室分别进行三维重建和可视化,利用软件自带工具计算出各区及侧脑室体积。结果 (1)大鼠海马结构起自于前囱后1.4mm或对耳线前7.6mm,止于前囱后6.8mm或对耳线前2.2mm,全长5.4mm;(2)侧脑室呈"C"形位于海马外侧,齿状回位于中线两侧,CA1区位于海马的顶部,CA2区位于CA1区的外侧,CA3区位于CA2与齿状回之间;(3)海马内各区体积CA1为(8.634 9±0.092 7)μL,CA2为(2.952 2±0.058 7)μL,CA3为(3.756 9±0.061 4)μL,DG为(8.547 9±0.1390)μL,侧脑室体积为(2.143 5±0.040 8)μL。结论利用组织学方法可以对大鼠脑内海马结构及其各区进行三维可视化重建;利用3D-DOCTOR 4.0软件可以计算重建的海马各区体积。

Objective To explore the applicative values of histological method in rat hippocampus 3D reconstruction.Methods We obtained three whole rat brains specimen（from the top to the C1st segment of spinal cord） from adult SD rats.Two brains were continuously sectioned in coronary plan,the other one in sagittal plan,and every slice was 30 μm thick.All the slices had been stained with Nissl staining,and photographed via 5 multiply objective scope.Every slice was divided into four to five scopes,all of the photos were stitched and calibrated via three-axes locating system in Photoshop7.0（Adobe corporation）.The hippocampus were divided into CA1,CA2,CA3 and DG parts referring to the stereoscopic atlas of rat brain.Each part and lateral ventricles were then reconstructed and visualized,volumes were calculated by the tools in 3D-DOCTOR4.0.Results（1） Rat hippocampus started from 1.4 mm behind the bregma or 7.6 mm before the ear and ended in6.8 mm behind the bregma or 2.2 mm before the ear,the whole length was 5.4 mm.（2） Lateral ventricles（LV） were located laterally to hippocampus,dental gyrus（DG） was located near the middle line,CA1 was located in the top of hippocampus,CA2 was located laterally to CA1,CA3 was located between CA2 and DG.（3） The volumes of the four parts in hippocampus were（8.634 9±0.092 7） μL in CA1,（2.952 2±0.058 7） μL in CA2,（3.756 9±0.061 4） μL in CA3,and（8.547 9±0.139 0） μL in DG.The volume of LV was（2.143 5±0.040 8） μL.Conclusions The four parts of hippocampus can be reconstructed by histological method.The volumes of the four reconstructed parts can be calculated in 3D-DOCTOR4.0.