Abstract: | To elucidate the signal transduction mechanisms in the turtlevomeronasal receptor neurons, the effects of forskolin, changesin mucosal Ca2+ concentrations and ruthenium red on the responsesof the accessory olfactory bulb to general odorants were examined.Forskolin elicited a large response, suggesting that there arecAMP-gated channels in the vomeronasal neurons. On the otherhand, the dependence of the responses to general odorants onCa2+ concentrations was different from that of the responseto forskolin. A large response to an odorant (n-amyl acetate)appeared after the cAMP-mediated pathway was fully desensitizedby application of 50 µM forskolin. These results suggestthat the cAMP-mediated pathway does not contribute significantlyto generation of the response to general odorants. A concentrationof 50 µM ruthenium red significantly reduced the responsesto n-amyl acetate alone and after 50 µM forskolin desensitization,suggesting that the inositol triphosphate-mediated pathway contributespartly to generation of the responses to general odorants inthe vomeronasal neurons. Chem Senses 21: 763771, 1996. |