Lin S C, Olson K C, Okazaki H, Richelson E
J Neurochem. 1986 Jan;46(1):274-9. doi: 10.1111/j.1471-4159.1986.tb12958.x.
Pirenzepine, a potent antimuscarinic agent with apparent selectivity for a subtype (M1) of muscarinic receptors, was used in tritiated form to characterize its binding to human brain tissue. Specific [3H]pirenzepine binding showed rapid association and dissociation. From kinetic and competitive binding experiments, its KD was 5.5 nM and 9 nM, respectively. Regional distribution of [3H]pirenzepine binding determined in parallel with [3H]quinuclidinyl benzilate binding, a nonselective muscarinic antagonist, indicated a significant correlation for the maximum number of binding sites for the two radioligands in 13 brain regions, with the highest amount of binding for each in the putamen and the least in the cerebellum. Binding for [3H]pirenzepine averaged 57% of that for [3H]quinuclidinyl benzilate, with a range of 20% (cerebellum) to 77% (frontal cortex). Most antidepressants and neuroleptics tested had affinities for [3H]pirenzepine binding sites that were not significantly different from their previously reported values obtained with the use of [3H]quinuclidinyl benzilate.
哌仑西平是一种对毒蕈碱受体的一个亚型（M1）具有明显选择性的强效抗毒蕈碱剂，它以氚化形式用于表征其与人脑组织的结合情况。特异性[3H]哌仑西平结合表现出快速的结合和解离。从动力学和竞争性结合实验来看，其解离常数（KD）分别为5.5纳摩尔和9纳摩尔。与非选择性毒蕈碱拮抗剂[3H]喹核醇基苯甲酸酯结合平行测定的[3H]哌仑西平结合的区域分布表明，在13个脑区中，两种放射性配体的最大结合位点数存在显著相关性，每种配体在壳核中的结合量最高，在小脑中最少。[3H]哌仑西平的结合平均为[3H]喹核醇基苯甲酸酯结合的57%，范围为20%（小脑）至77%（额叶皮质）。所测试的大多数抗抑郁药和抗精神病药对[3H]哌仑西平结合位点的亲和力与它们先前使用[3H]喹核醇基苯甲酸酯获得的报道值没有显著差异。
