Skoglund T S, Pascher R, Berthold C H
Institute of Anatomy and Cell Biology and MEDNET-Laboratory, University of Goteborg, Medicinaregatan 3, Sweden.
Neurosci Lett. 1996 Apr 19;208(2):97-100. doi: 10.1016/0304-3940(96)12569-6.
We have investigated the number of neurons in three neocortical areas of the rat brain. Our results challenge the uniformity concept proposed by Rockel et al. [Brain, 103 (1980) 221-244]. Area Fr1, HL and Oc2 (primary motor, primary somatosensory and secondary visual cortex) from Sprague-Dawley rats were examined. The brains were glutaraldehyde fixed, sectioned in 50 mu m thick sagittal slices and stained in Richardson's solution. The counting was carried out using a computerized system based on the optical disector. The cortical thickness was measured to be 1.9 mm, 1.9 mm, and 1.4 mm in area Fr1, HL, and Oc2, respectively. The number of neurons under 1 mm2 cortical surface was calculated to be 91 100 in Fr1, 133 500 in HL and 106 100 in Oc2. The number of neurons in a volume of tissue 30 x 25 mu m through the depth of the cortex was calculated to be 68 in Fr1, 100 in HL and 80 in Oc2. The density of neurons was calculated to be 48 500 neurons/mm3 in Fr1, 69 400 neurons/mm3 in HL and 76,900 neurons/mm3 in Oc2. There were significant (P < 0.01) differences between all areas regarding both the number of neurons under a certain area of surface as well as the neuron density. The results indicate that there is no basic uniformity in the number of neurons under a certain area of cortical surface.
我们研究了大鼠大脑三个新皮层区域的神经元数量。我们的结果对Rockel等人[《大脑》，103 (1980) 221 - 244]提出的一致性概念提出了挑战。对来自Sprague - Dawley大鼠的额叶1区（初级运动皮层）、顶叶1区（初级躯体感觉皮层）和枕叶2区（次级视觉皮层）进行了检查。大脑用戊二醛固定，切成50微米厚的矢状切片，并用理查森溶液染色。计数使用基于光学分割器的计算机系统进行。额叶1区、顶叶1区和枕叶2区的皮层厚度分别测量为1.9毫米、1.9毫米和1.4毫米。计算得出，每1平方毫米皮层表面下的神经元数量在额叶1区为91100个，在顶叶1区为133500个，在枕叶2区为106100个。计算得出，在贯穿皮层深度为30×25微米的组织体积中的神经元数量在额叶1区为68个，在顶叶1区为100个，在枕叶2区为80个。计算得出的神经元密度在额叶1区为48500个神经元/立方毫米，在顶叶1区为69400个神经元/立方毫米，在枕叶2区为76900个神经元/立方毫米。在所有区域之间，无论是特定面积表面下的神经元数量还是神经元密度，均存在显著差异（P < 0.01）。结果表明，在特定面积的皮层表面下，神经元数量不存在基本的一致性。
