Fig. 2.

cAMP and Ca²⁺ dynamics in OSN in response to odors. Conditions as in Fig. 1. (A) Odor mixture (200 μM) was applied to the bath in normal Ringer's solution. (C) As in (A) but in Ca²⁺ free Ringer's solution. (E) odor puff focally applied to the growth cone. (B) and (D) time for half-maximal response (t_1/2) for the related treatment, in (B) dendrite-soma P = 0.02*, cone-soma P = 0.006**; in (D) dendrite-soma P = 0.004**, cone-soma P = 0.002**; bars, SEM. (F) Example of OSN nonresponsive to the local odor puff but responsive to forskolin, bath applied. In (G) and (I), normalized fluorescence ratio changes (340 nm/380 nm) in two OSN loaded with Fura 2-AM and challenged with an odor puff focally applied to the growth cone. The same neurons of panel (G) and (I) were rechallenged with an odor puff in the presence of H, CNG channel blocker MgCl₂ (10 mM) or J, AC blocker, SQ22536 (30 μM). (K and L) Summary of responses (%), (i) P = 0.002**, (L) P = 0.001**, bars, SEM. Green line, axon termini-growth cone; pink line, soma; blue line, cilia-dendrite.