Establishment of a method how to calculate the absolute number of neurotransmitter receptors acuroadiogaphically imaged

体外宏观放射自显影是确定中枢神经系统各盘状区神经递质受体分布的最佳方法，也是唯一的方法。本研究的目的是建立使用氚屈光标准计算脑放射自显影图像中受体绝对数的方法。实际上，标准化是通过与M受体的拮抗剂~3H-QNB结合来完成的。制备正常大鼠脑组织匀浆，将部分ISA与~3H-QNB孵育，计算以摩尔/mg蛋白表示的结合。按照宏观放射自显影的一般过程，将其余的孵育液进行中心化处理，将得到的小球涂抹到氢敏胶片上。我们利用Zeiss公司的IBAS II计算机系统来确定放射自显影的光密度与放射性的关系。作为结果，我们注意到，当转换为In-In标度时，光密度与组织结合放射性之间存在线性关系。通过这些实验，我们获得了由体外放射自显影计算的受体绝对数与通过脑匀浆结合实验计算的受体绝对数之间非常好的一致性。这意味着我们制备的标准品具有良好的质量，可以作为体外放射自显影的定量标准品。通过我们所推崇的这一新技术，我们研究了MPTP诱导的猴子帕金森病、人类脊髓小脑变性和阿尔茨海默病以及这些神经障碍的动物模型中各种神经递质受体的分布。此外，还观察了大鼠脑内乙酰胆碱受体亚型和神经降压素受体的个体发育。通过这些实验，证实了体外定量放射自显影是一种可靠的、广泛适用于神经科学的实验技术。

in vitro Macro-autoradigraphy is the best and only method to determine distrbution of neurotransmitter receptors in each discete region within the central nervous system. The purpose of this research is to establish the method to calculate the absolute number of receptors in autoradiographic images of the brain using tritiated rediactive standards. Actually, Standaedizartion was done by binding of 3H-QNB which is an antabonist of muscatineic acetylcholine receptor. Homogenate of the normal rat brain was prepared adn part of isa was incubated with^3H-QNB to calculate the binding expressed as mol/mg protein. The rest of incubated solution was centriguged and the obtained pellet was applied to a H-sensitive film according to the ordinary process of macro-autoradiography. We utilized the IBAS II computer system of Zeiss company to determine relationship between autoradiographic optical density and radioactivity. As the results, we noticed that there was a linewar relationship between optical density and tissue-bound radioactivity when converted to a In-In scale. With these experiments, we obrained a very good consistence between the absolute number of receptore calculated from in vitro autoradioragraphy and that from brain homogenate binding experiments. This means that the standard prepared by us has a good quality enough to use as a standard of quantitative in vitro autoradiography. Through this rechnique esteblished by us, we examined distributions of various neurotransmitter receptors in the brains of MPTP-induced monkey parkinsonism, human cases of spinocerebellar degenetation and Alzheimer disease, and animal models of these neurological desorders. Besids, ontogenic developments of muscatinic acetylcholine receptor subtypes and neutotensin receptors in rat brains were examined. Throught these experiments, is was confirmed thast quantitative in vitro autoradigrraphy is a reliable and widely applicable experimental technique in neuroscience.