Basic research of simultaneous evaluation of dopaminergic receptor and presynaptic neuronal functions in the brain using autoradiography

本研究旨在探讨帕金森病模型大鼠多巴胺转运体放射自显影与酪氨酸羟化酶免疫染色的关系。方法：将6-OHDA立体定向注入帕金森病模型大鼠一侧黑质，观察阿朴吗啡诱导的大鼠顺时针旋转行为。连续脑切片进行抗酪氨酸羟化酶（TH）抗体的免疫染色和多巴胺能系统的放射自显影。多巴胺D1，D2受体和转运蛋白密度分别采用SCH，YM和GBR成像板放射自显影进行评估。免疫组化切片用光学数字图像分析仪分析，放射自显影用成像平板分析仪分析。以尾壳核损伤侧与对侧的比值为指标。统计分析阿扑吗啡诱导的旋转、TH免疫染色、多巴胺D1、D2受体和转运蛋白之间的相关性。结果：旋转度、TH与GBR呈显著正相关，GBR较TH和旋转度敏感。结论：多巴胺转运体显像较TH和旋转敏感。这一结果支持多巴胺转运蛋白成像可以检测到早期疾病，而没有明显的症状。

The aim of this study is to clarify the relationship between dopamine transporter autoradiography and tyrosine hydroxylase immunostaining in experimental unilateral parkinsonian model rat. Method : Parkinsonian model rats were stereotactically infused 6-OHDA into unilateral substantia nigra, and evaluated clockwise rotation behavior induced by administration of apomorphine. Sequential brain sections underwent immunostaining using anti-tyrosine hydroxylase (TH) antibody and autoradiography of dopaminergic system. Dopamine D1, D2 receptors and transporter density was assessed by imaging plate autoradiography using SCH, YM and GBR, respectively. Immunostained section were analyzed by optical digital imaging analyzer, and autoradiography were analyzed by imaging plate analyzer. Ratios of lesioned side value to contralateral side value in the caudate-putamen were used as indices. Correlations among apomorphine-induced rotation, TH immunostaining, dopamine D1, D2 receptors and transporter were analyzed statistically. Results : Significant positive correlations were shown between rotation, TH and GBR.GBR was more sensitive than TH and rotation. Conclusion : Dopamine transporter imaging is more sensitive than TH and rotation. This results support that dopamine transporter imaging may detect an early disease without obvious symptoms.