In Vivo Significance of In Vitro Studies on G-Protein-Coupled Receptor Heteromers.

Interactions between distinct receptor proteins have been assessed in vitro and in vivo. Among these studies are G-Protein-Coupled Receptor (GPCR) heteromers. GPCR heteromers form a popular area for study in molecular pharmacology and are expected to contribute valuable information to clinical needs for development of medications discovery in various neuropsychiatric diseases and symptoms. For example, physical formation of GPCR heteromers could result in a novel signaling mechanism that is distinct from those of individual GPCR monomers or their homomer. However, significance of various studies on dopamine (DA) D1/D2 receptor heteromers was challenged by a recent report [1]. Javitch et al. [1] provided compelling evidence against D1/D2 heteromers, one of the most prominent subjects of interest in neuropsychiatry field.