FIG. 5.

PACAP-elicited calcium responses in adult cultures and neonatal slices of mouse olfactory epithelium. A: ratiometric fura imaging experiments were performed on adult mouse ORN cultures using 6 coverslips obtained from 3 different mice. A representative trace shows increases in intracellular Ca²⁺ in response to 100 nM PACAP, high K⁺ Ringer, 25 μM n-amyl acetate + 50 μM R-carvone (odors), and 10 μM ATP. B: 2 traces obtained from a slice of P4 mouse OE loaded with fluo-4 AM are shown. Test solutions (1:1,000 fluorescein; 100 nM PACAP; 25 μM n-amyl acetate + 50 μM R-carvone (odors); high K⁺ Ringer; Ringer control; 10 μM ATP) were loop injected into bath flow (15- to 20-s delay) at the arrowheads. There was a 4-min wash between test substance application (data not shown). The data are expressed as a percent change in fluorescence over the baseline (%ΔF/F). Traces were obtained from the ORNs outlined in C. C: pseudocolor confocal images taken at the times indicated by the asterisks on the PACAP trace in B. Control (left) was before PACAP application, PACAP (middle) was during the peak of the response, and Wash (right) was following superfusion of PACAP onto the slice. Fluorescent cells along the surface are sustentacular cells that have loaded with fluo-4. Scale bar, 50 μm.