Fig. 7. Application of the phospholipase C inhibitor U-73122 (1 µmol l^–1) differentially affected odorant-evoked electro-olfactogram (EOG) responses. (A) Example responses elicited by glutamine, spermidine and TCA in an AFW background (left traces) or in the presence of U-73122 (right traces). (B) Summary changes in odor-evoked responses in the presence of U-73122 normalized to the pre-drug treatment level. U-73122 had little effect on taurocholic acid-, AGB- and spermidine-evoked responses, suggesting that the phospholipase C activation is not critical during the initial transduction of bile salt or polyamine input. Amino acid-evoked responses were significantly reduced to 20–50% of their pre U-73122 levels. Asterisks designate responses significantly reduced compared to the paired pre U-73122 responses (paired t-test, P<0.05). Values are means ± S.E.M. Abbreviations as in Fig. 1.