Kondo S, Morita T
Second Department of Biochemistry, Akita University School of Medicine.
Nihon Hinyokika Gakkai Zasshi. 1993 Jul;84(7):1255-61. doi: 10.5980/jpnjurol1989.84.1255.
The subtypes of the muscarinic cholinergic receptor in human detrusor muscle were studied using radioligand binding techniques. It was found that there were significant amount of M1, M2 and M3 receptors labeled by 3H-pirenzepine, 3H-AFDX and 3H-4DAMP, respectively, in human detrusor muscle. The rank order of the amount of these receptors was M3 > M1 > or = M2. The amount of M3 receptors was about 10-fold of M1 or M2. In the inhibition experiment of 3H-QNB binding to human detrusor muscle, the Ki values of pirenzepine or AFDX was 50-100 fold of that of 4DAMP and the rank order of Ki values was pirenzepine > AFDX > 4DAMP. The M3 selective drug, 4DAMP showed smallest Ki value among the three drugs studied, indicating that the affinity of M3 receptor was highest among the three muscarinic subtypes. These data suggest that M3 receptors are predominant in human detrusor muscle biochemically.
采用放射性配体结合技术研究了人逼尿肌中毒蕈碱型胆碱能受体的亚型。结果发现，在人逼尿肌中，分别有大量的M1、M2和M3受体被3H-哌仑西平、3H-AFDX和3H-4DAMP标记。这些受体数量的排序为M3>M1≥M2。M3受体的数量约为M1或M2的10倍。在3H-QNB与人逼尿肌结合的抑制实验中，哌仑西平或AFDX的Ki值是4DAMP的50-100倍，Ki值的排序为哌仑西平>AFDX>4DAMP。M3选择性药物4DAMP在所研究的三种药物中显示出最小的Ki值，表明M3受体在三种毒蕈碱亚型中的亲和力最高。这些数据表明，从生化角度来看，M3受体在人逼尿肌中占主导地位。
