The neuronal functions are mostly based on molecular processes that are determined by a variety of genetic programs. Therefore, the description of neural functions at the molecular level plays a pivotal role in arriving a functional definition of the molecular nets operating within neural cells and cell networks. Our scientific activities are centred on the analysis of the molecular mechanisms involved in regulation of signal transduction via G-protein coupled receptors (GPCRs). The strategic aim of our research projects is understanding of time- and space-dependent interaction between receptors and their downstream effectors, leading to the specific actions within the neuronal cell. One of the major goals is the dynamic on-line measurement of signaling processes to enable a quantitative correlation with physiological and morphological neuronal functions. As a model system we use signalling processes mediated by different GPCRs including serotonin and opioid receptors.