PAM expression in the developing and adult olfactory epithelium. A, Immunohistochemistry on E13 paraffin section using an affinity-purified antibody against Exon A of PAM. The separation between the developing olfactory epithelium and lamina propria is indicated by a dotted line.B, Bouin's fixed adult (Ad) rat olfactory epithelium immunostained using an affinity-purified antibody against PHM. Neurons (n) and sustentacular cells (s) are indicated. C, High magnification view of the adult olfactory epithelium demonstrating PAM localization to the perinuclear area within the cell bodies of neuronal (n) and sustentacular (s) cells. D, In situ hybridization of adult olfactory epithelium using an antisense probe directed against the 3′-untranslated region of PAM. Signal is apparent in all regions of the olfactory epithelium, including the basal layer of cells.E, Immunohistochemistry specificity control using immunodepleted antibodies against Exon A (E13) or PHM (Ad). F, High magnification of adult olfactory epithelium for antisense (AS) and sense (S) control in situ hybridization. Scale bars: A, B, D, 25 μm; C, 12.5 μm. Box lengths: E, F, 50 μm.