Existence of multiple receptors in single neurons: responses of single bullfrog olfactory neurons to many cAMP-dependent and independent odorants.
The responses of single bullfrog olfactory neurons to various odorants were measured with the whole-cell patch clamp which offers direct information on cellular events and with the ciliary recording technique to obtain stable quantitative data from many neurons. A large portion of single olfactory neurons (about 64% and 79% in the whole-cell recording and in the ciliary recording, respectively) responded to many odorants with quite diverse molecular structures, including both odorants previously indicated to be cAMP-dependent (increasing) and independent odorants. One odorant elicited a response in many cells; e.g. hedione and citralva elicited the response in 100% and 92% of total neurons examined with the ciliary recording technique. To confirm that a single neuron carries different receptors or transduction pathways, the cross-adaptation technique was applied to single neurons. Application of hedione to a single neuron after desensitization of the current in response to lyral or citralva induced an inward current with a similar magnitude to that applied alone. It was suggested that most single olfactory neurons carry multiple receptors and at least dual transduction pathways.
Kashiwayanagi
M
M
Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan. yanagi@ph.hines.hokudai.ac.jp
Shimano
K
K
Kurihara
K
K
D000222:Adaptation, Physiological; D000818:Animals; D000242:Cyclic AMP / Q000502:physiology*; D066298:In Vitro Techniques; D009812:Odorants; D018034:Olfactory Receptor Neurons / Q000187:drug effects* / Q000378:metabolism; D018408:Patch-Clamp Techniques; D011892:Rana catesbeiana; D018035:Receptors, Odorant / Q000187:drug effects* / Q000378:metabolism; D013268:Stimulation, Chemical
D018035:Receptors, Odorant; D000242:Cyclic AMP