The role of c-fos gene disruption on binding characteristics of selected G protein-coupled receptors has been investigated. The following receptors were studied: muscarinic receptors (MR), alpha1-adrenoceptors (AAR), beta-adrenoceptors (BAR), D1-like dopamine receptors (D1R), D2-like dopamine receptors (D2R).
We have tested the hypothesis that c-fos gene disruption would not influence the receptor density in central nervous system (CNS: brain cortex and cerebellum) and in the periphery (lung, heart). We found that both in the periphery and in the CNS there were important changes in receptor density.
Both MR and BAR were increased in the lung and heart. The effects of c-fos gene disruption in CNS were more selective.
In general, the receptors that activate Gq-phospholipase C-proteinkinase C pathway (AAR, MR) were affected, while the others (that activate/or inhibit adenylyl cyclase: BAR, D1R, D2R) were not. These results show that disruption of c-fos gene could significantly change the expression of G protein-coupled receptors.
Moreover, these changes could be comprehended as one of the adaptive mechanisms that help the organism to cope with c-fos gene disruption.