Hsieh Y L, Hsu C, Lue S I, Hsu H K, Peng M T
Department of Physiology, Kaohsiung Medical College, Taiwan, ROC.
Dev Neurosci. 1997;19(4):342-7. doi: 10.1159/000111231.
The neurotoxic effect of monosodium L-glutamate (MSG) on the morphologies in the darkly stained sexually dimorphic nucleus of the preoptic area (SDN-POA) and the lighter-staining surrounding area (non-SDN-POA) within the medial preoptic nucleus (MPN) was evaluated. Male and female Long-Evans rats were used. MSG (4 mg/g of body weight) was administered subcutaneously to pups on days 1 and 3 postnatally. Normal saline was used as the vehicle. At the age of 6 months, the rats were sacrificed and the brain tissues were fixed for histological examination. The morphological changes, i.e., total volume, density, total neuron number, neuronal nuclear volume (NNV) and ratio of pyknosis, of the SDN-POA and non-SDN-POA within the MPN, were estimated using the AMS VIDS III semiautomatic image-analytic system. The results indicate that neonatal MSG treatment caused significant neuronal loss and decreases in total volume of the SDN-POA and non-SDN-POA of male and female rats. However, only the SDN-POA of MSG-treated male rats showed a significant increase of pyknosis and decrease of neuronal density. A significant enlargement of NNV in the SDN-POA and non-SDN-POA was observed in the MSG-treated male rats. These results indicate that the MPN shows sex-specific and area-specific changes after neonatal neurotoxicity due to MSG.
评估了L-谷氨酸单钠（MSG）对视前内侧核（MPN）中染色较深的视前区性二态核（SDN-POA）和染色较浅的周围区域（非SDN-POA）形态的神经毒性作用。使用雄性和雌性Long-Evans大鼠。在出生后第1天和第3天，给幼崽皮下注射MSG（4mg/g体重）。使用生理盐水作为溶剂。在6个月龄时，处死大鼠并固定脑组织以进行组织学检查。使用AMS VIDS III半自动图像分析系统估计MPN内SDN-POA和非SDN-POA的形态变化，即总体积、密度、总神经元数量、神经元核体积（NNV）和固缩比例。结果表明，新生期MSG处理导致雄性和雌性大鼠的SDN-POA和非SDN-POA出现明显的神经元丢失和总体积减少。然而，仅MSG处理的雄性大鼠的SDN-POA显示固缩显著增加且神经元密度降低。在MSG处理的雄性大鼠中，观察到SDN-POA和非SDN-POA中的NNV显著增大。这些结果表明，由于MSG导致的新生期神经毒性后，MPN表现出性别特异性和区域特异性变化。
