Distribution of PDE4A and B-o alpha immunoreactivity in the accessory olfactory system of the mouse

Distribution of the cAMP-specific phosphodiesterase PDE4A was examined in t he accessory olfactory system by immunohistochemistry. Adjacent sections th rough the vomeronasal organ (VNO) and accessory olfactory bulb (AOB) were a lternately immunostained with antibodies against PDE4A or the G-protein a s ubunit G(o alpha), which labels basal VNO neurons, in order to determine wh ether PDE4A occurs preferentially in one of two segregated VNO pathways. We found that PDE4A strongly labeled apical VNO neurons and rostral AOB glome ruli. There was virtually no overlap in G(o alpha) and PDE4A staining, and there were no regions of the VNO neuroepithelium or AOB glomeruli not label ed by either antibody. These results identify a potential member of the phe romone transduction cascade in apical neurons, and provide further evidence that the VNO consists of functionally distinct pathways. NeuroReport 11:27 -32 (C) 2000 Lippincott Williams & Wilkins.