Regulation of Ca2+ concentration by second messengers in newt olfactory receptor cell.
The role of IP3 in olfactory transduction is controversial. This issue was addressed by measuring intracellular Ca2+ concentration under voltage clamp in newt olfactory receptor cells. Odorant stimulation and dialysis of cells with cyclic AMP (cAMP) caused an increase in intracellular Ca2+ concentration that originated in the cilia, as expected from previous works. However, dialysis with IP3 caused a slower rise in Ca2+ concentration that originated in the cell body. Our results suggest that IP3 influences transduction by regulating the intracellular Ca2+ concentration, rather than by carrying the transduction current.
Nakamura
T
T
Department of Applied Physics and Chemistry, University of Electro-Communications, Tokyo, Japan.
Tsuru
K
K
Miyamoto
S
S
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000378:metabolism / Q000502:physiology; D000242:Cyclic AMP / Q000502:physiology; D016257:Fura-2; D015544:Inositol 1,4,5-Trisphosphate / Q000502:physiology; D017551:Microdialysis; D009831:Olfactory Mucosa / Q000166:cytology; D018035:Receptors, Odorant / Q000502:physiology*; D012455:Salamandridae; D015290:Second Messenger Systems / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology
D015220:Calcium Channels; D018035:Receptors, Odorant; D015544:Inositol 1,4,5-Trisphosphate; D000242:Cyclic AMP; D002118:Calcium; D016257:Fura-2