Brusa R, Gamalero S R, Genazzani E, Eva C
Istituto di Farmacologia e Terapia Sperimentale, University of Torino, Italy.
Eur J Pharmacol. 1995 Mar 15;289(1):9-16. doi: 10.1016/0922-4106(95)90162-0.
The homologous regulation of the muscarinic m1 and m3 receptors mRNA was studied in rat corticostriatal neuronal cultures. In response to the full agonist carbachol the m1 and m3 receptor mRNA levels were modulated and showed different time-courses. The m1 receptor mRNA increased to 270% of prestimulation levels after 6 h, while the m3 receptor transcript transiently increased to 170% after 2 h. Conversely, the muscarinic receptor partial agonist oxotremorine caused a rapid and sustained increase in both mRNA species as soon as after 1 h of exposure. A comparable increase in both receptor mRNAs was induced by the partial agonist [4-(m-chlorophenylcarbamoyloxy)-2-butynyltrimethyl-ammonium chloride] (McN-A-343). The observation that 1 h exposure to the non selective antagonist N-methyl-scopolamine also enhanced the m1 and m3 receptor transcripts suggests that in corticostriatal neurons muscarinic receptor partial agonists exert an antagonist-like effect on the m1 and m3 receptor mRNAs.
在大鼠皮质纹状体神经元培养物中研究了毒蕈碱型m1和m3受体mRNA的同源调节。响应于完全激动剂卡巴胆碱，m1和m3受体mRNA水平受到调节并呈现出不同的时间进程。m1受体mRNA在6小时后增加至刺激前水平的270%，而m3受体转录本在2小时后短暂增加至170%。相反，毒蕈碱受体部分激动剂氧化震颤素在暴露1小时后就立即引起两种mRNA种类的快速且持续增加。部分激动剂4-(间氯苯基氨甲酰氧基)-2-丁炔基三甲基氯化铵诱导两种受体mRNA产生类似的增加。暴露于非选择性拮抗剂N-甲基东莨菪碱1小时也增强了m1和m3受体转录本，这一观察结果表明，在皮质纹状体神经元中，毒蕈碱受体部分激动剂对m1和m3受体mRNA发挥类似拮抗剂的作用。
