慢性镉中毒小鼠中脑黑质的形态学研究

目的：观察慢性镉中毒中脑黑质形态学变化。方法：进行HE染色，尼氏染色，酷氨酸羟化酶（Tyrosine hydroxylase TH)免疫组化染色，用光镜观察，并对TH免疫组化染色阳性反应神经元进行形态计量分析；部分小鼠中脑黑质超薄切片，经透射电镜观察。结果：中脑黑质受损，主要病理变化有：（1）神经元变化。（2）神经元坏死，（3）多巴胺能神经元数量减少，多巴胺合成也减少。（4）软化灶形成。（5）局部区域出现炎症反应。在上述慢性镉中毒致小鼠中脑黑质损伤的病理变化，与帕金森病（Parkinson‘s disease PD)的主要临床病理改变相类似。结论：提示镉可能是诱发PD的病因之一。

Morphological Study on Substantia Nigra of Mice Intoxicated with Cd Chronically

Objective To observe the microstructure of the substantia nigra of mice chronically intoxicated with Cd.Methods Light microscopy and trasmission electorn microscopy were used.The TH-positive neurons in the substantia nigra were analyzed with morphometric technique.Results (1)Most neurons were degenerated.The nuclei appeared pycnosis and deformation.The heterochromatins were increased and migrated to the marginal zone of the nuclei.The nissl bodies(rough surfaced endoplasmic reticulum and free ribosome) and other organelles in the parikaryon obvously were decreased.(2) A few necrotic neurons were found.The nuclear envelopes were broken and the nuclei were dissolved.The Nissl bodies and other organelles in the parikaryon were disappeared.(3)The quantity of dopamine neurons and the dopamine producted by them were decreased.(4)There were the softening focuses in the substantia nigra.The boundary of the focuses were clear.Some neurons were dissolved and some neurons were degenerated in the focuses.(5)The inflammation were seen in the substantia nigra.Numberous limphocytes were appeared in the inflammatory areas.The lymphocytes formed an sheath in the periphery of small blood vessel.These findings indicated that the substantia nigra is a target of chronic Cd toxicity and alterations of the microstructure of the substantia nigra by chronic Cd toxicity(especially the quantity of dopamine neurons and the dopamine producted by them were decreased) are similar to the pathological charateristics of Parkinson's disease.Conclusion Cadmium would be one of the factors induced Parkinson's disease.