Fig. 4.

GC-B and CNP are positioned to play a role in ORN development and regeneration. Cryosections of adult olfactory epithelium and bulb were immunostained for GC-B or CNP. A, C, Staining of adult rat olfactory epithelium with anti-GC-B antibody indicated that GC-B was expressed in more mature cells found in the upper layer of the epithelium (A) and within cells of and migrating out of the basal cell layer (C). This pattern was also seen in P1 mouse pups, although the staining was lighter and more diffuse (data not shown).F, Immunostaining of the adult rat olfactory bulb with anti-GC-B antibody demonstrated that GC-B does not appear to be present in the bulb. B, Immunostaining of the adult rat olfactory epithelium with anti-CNP antibody showed that CNP was expressed in sustentacular cell processes and foot pads. Intense staining is also seen within axon bundles within the lamina propria (E) and leading into the olfactory bulb (D). Within the epithelium of P1 rat pups, CNP was present within scattered cells, both mature and immature, throughout the epithelium (data not shown). G, Immunostaining of the adult bulb with anti-CNP antibody demonstrated expression of CNP in periglomerular cells surrounding the glomeruli. Within the adult olfactory bulb, cells of the mitral cell layer were also densely stained (data not shown). Within P1 rat pups, staining is also seen within the forming glomeruli and within the mitral cell layer (data not shown). Staining was performed on 5–10 sections from each of two to three rats from both P1 pups and adult animals.H, cGMP production in response to CNP added to primary cultures of P1 rat ORNs. n = 2 values per dose from triplicate experiments.