Quintero Gabriel C, Spano Daniela, Lahoste Gerald J, Harrison Laura M
Department of Psychology, University of New Orleans, New Orleans, Louisiana, USA.
Neuroreport. 2008 Oct 29;19(16):1563-6. doi: 10.1097/WNR.0b013e3283118434.
Dopamine activates five different receptor subtypes and a complex array of intracellular signaling pathways. Rhes is a striatally expressed guanidine triphosphate-binding protein involved in dopamine signaling. Here we have used mutant mice to test whether Rhes (Ras homolog enriched in striatum) is involved in D1 and D2 dopamine receptor-mediated behaviors. Rhes was not necessary for the expression of normal D1/D2 receptor synergism, as measured by apomorphine-induced stereotypy. The stereotypic responses to D1/D2 costimulation and to D2 stimulation alone were significantly increased in mice lacking Rhes, but D1 receptor-mediated grooming was reduced in these mice. These results suggest that Rhes is normally inhibitory to behaviors induced by D1/D2 receptor costimulation and by D2 receptor stimulation alone. Rhes, however, seems to facilitate the D1-specific behavior of grooming.
多巴胺激活五种不同的受体亚型以及一系列复杂的细胞内信号通路。Rhes是一种在纹状体中表达的鸟苷三磷酸结合蛋白，参与多巴胺信号传导。在此，我们利用突变小鼠来测试Rhes（富含纹状体的Ras同源物）是否参与D1和D2多巴胺受体介导的行为。通过阿扑吗啡诱导的刻板行为来衡量，Rhes对于正常D1/D2受体协同作用的表达并非必需。在缺乏Rhes的小鼠中，对D1/D2共刺激和单独D2刺激的刻板反应显著增加，但这些小鼠中D1受体介导的梳理行为减少。这些结果表明，Rhes通常对由D1/D2受体共刺激和单独D2受体刺激诱导的行为具有抑制作用。然而，Rhes似乎促进了梳理这种D1特异性行为。
