Analysis of muscarinic receptor function using knockout mice

Research Project

Project/Area Number	11670083
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	General pharmacology
Research Institution	The University of Tokyo
Principal Investigator	MATSUI Minoru Graduate School of Pharmaceutical Sciences, The University of Tokyo, Assistant Professor, 大学院・薬学系研究科, 助手 (50282611)
Co-Investigator(Kenkyū-buntansha)	SASAKI Nobuya Graduate School of Pharmaceutical Sciences, The University of Tokyo, Assistant Professor, 大学院・薬学系研究科, 助手 (20302614) TAKAKU Kazuaki Department of Pharmacology, Kyoto University Graduate School of Medicine, Assistant Professor, 大学院・医学研究科, 助手 (90313121) TAKETO Makoto Department of Pharmacology, Kyoto University Graduate School of Medicine, Professor, 大学院・医学研究科, 教授 (70281714)
Project Period (FY)	1999 – 2000
Project Status	Completed (Fiscal Year 2000)
Budget Amount *help	¥3,400,000 (Direct Cost: ¥3,400,000) Fiscal Year 2000: ¥1,300,000 (Direct Cost: ¥1,300,000) Fiscal Year 1999: ¥2,100,000 (Direct Cost: ¥2,100,000)
Keywords	acetylcholine / knockout mice / muscarinic receptor / parasympathetic nervous system
Research Abstract	As for subtype 1, we have just established the knockout mice. As for subtype 2, we have backcrossed the knockout mice to both C57BL/6J and DBA/2J for more than five generations. As for subtype 3, we analyzed the phenotype of knocktout mice and found the following. 1) M3 is exclusively responsible for the cholinergic salivary secretion. 2) Ninty-five % of in vitro contractility by carbachol is mediated by M3. Urinary retention is eminent in the males but mild in the females, suggesting a considerable sex difference in the involvement of cholinergic signals in the micturition mechanism. 3) We have found no apparent disability in the reproduction and gastrointestinal functions. We further crossed M2 and M3 knockout mice and established a mutant line which lacks both M2 and M3, and we are analyzing their phenotypes. As for subtype 4, we have backcrossed the knockout mice to both C57BL/6J and DBA/2J for more than eight generations. As for subtype 5, we performed backcrossing for eight generations. We found a significant difference in the behavioral response to cocaine, which suggest an abnormality in the domaminergic neuron activities.