Unidad de Investigación Médica en Farmacología, UMAE Hospital de Especialidades, Centro Médico Nacional Siglo XXI, IMSS, México, D. F. Mexico.
Restor Neurol Neurosci. 2012;30(1):1-8. doi: 10.3233/RNN-2011-0605.
To analyze the cytoarchitectural characteristics of the remaining pyramidal neurons in the hippocampal CA1 subfield of rats, four months after global cerebral ischemia (GCI) and progesterone treatment.
Dendritic arborization, and density and shape of the dendritic spines of CA1 pyramidal neurons in brains of intact rats, or rats submitted 120 days earlier to GCI and treatment with progesterone (8 mg/kg) or its vehicle, at 15 min, and 2, 6, 24, 48, and 72 h after the onset of reperfusion, were analyzed in samples processed by a modified Golgi method.
Few impregnated CA1 pyramidal neurons were identified in the ischemic vehicle-treated rats, with a short apical dendrite devoid of bifurcations and dendritic spines. In contrast, the remaining CA1 pyramidal neurons sampled from ischemic progesterone-treated rats showed sinuously branched dendrites with similar number of bifurcations and whole density of spines, and higher proportional density of mushroom spines than those in the intact group.
These cytoarchitectural characteristics may underlie the long-term preservation of place learning and memory functions seen after ischemia and progesterone neuroprotective treatment, possibly compensating for the severe reduction in neuronal population.
分析全脑缺血（GCI）和孕酮治疗后 4 个月大鼠海马 CA1 区剩余锥体神经元的细胞构筑特征。
用改良的戈尔吉氏（Golgi）法处理样本，分析正常大鼠或 120 天前经历 GCI 并接受孕酮（8mg/kg）或其载体治疗的大鼠的大脑中 CA1 锥体神经元的树突分支、树突棘密度和形状。在再灌注后 15 分钟、2、6、24、48 和 72 小时时进行分析。
在缺血性载体处理的大鼠中，仅识别出少量被浸渍的 CA1 锥体神经元，其具有无分叉的短顶树突和树突棘。相比之下，从缺血性孕酮处理的大鼠中采样的剩余 CA1 锥体神经元表现出曲折分支的树突，具有相似数量的分叉和整个棘密度，蘑菇形棘的比例密度高于正常组。
这些细胞构筑特征可能是缺血和孕酮神经保护治疗后长期保留空间学习和记忆功能的基础，可能补偿了神经元群体的严重减少。
