Inhibition and enhancement of odorant-induced cAMP accumulation in rat olfactory cilia by antibodies directed against Gαs/olf- and Gαi-protein subunits

The odorant-induced accumulation of cAMP can be inhibited by antibodies directed against Gαs/olf. In contrast, antibodies raised against Gαi-subunits caused a strong enhancement of the odorant-induced cAMP accumulation. Western blotting and immunoelectron microscopy revealed the presence of both GαS/olf- and Gαi-subunits in rat cilia preparations. The existence of both stimulatory and inhibitory odorant-induced regulation of adenylyl cyclase activity in olfactory cilia may indicate that an initial integration of different odorant stimuli begins at the level of primary reactions in the same effector enzyme.