Optical monitoring of early appearance of spontaneous membrane potential changes in the embryonic chick medulla oblongata using a voltage-sensitive dye.
Using a voltage-sensitive merocyanine-rhodamine dye (NK2761) and a 12 x 12-element photodiode matrix array, we recorded optically spontaneous membrane potential changes in a slice preparation from the embryonic chick brain stem during early development. The spontaneous optical signals, related to membrane potential changes, showed a simple monophasic shape with a relatively long duration, and they were synchronized among the different regions in the medulla oblongata. The spontaneous signals were first detected from seven-day-old embryos, and were not present in six-day-old embryos. The spontaneous signals appeared sporadically, and their frequency was very low. Three modes of optical signals termed "singlet-mode", "doublet-mode", and "triplet-mode" were observed. In the doublet- and triplet-modes, the spatial pattern of the first signal was primarily similar to that of the singlet-mode signal, whereas the signal size and spatial extent of the second and third signals appeared to decay.
Komuro
H
H
Department of Physiology, Tokyo Medical and Dental University School of Medicine, Japan.
Momose-Sato
Y
Y
Sakai
T
T
Hirota
A
A
Kamino
K
K
D000818:Animals; D001583:Benzoxazoles; D001933:Brain Stem / Q000502:physiology; D002642:Chick Embryo; D006651:Histocytochemistry; D008526:Medulla Oblongata / Q000166:cytology / Q000196:embryology* / Q000502:physiology; D008564:Membrane Potentials / Q000502:physiology; D012236:Rhodanine / Q000031:analogs & derivatives; D053778:Thiazolidines
D001583:Benzoxazoles; D053778:Thiazolidines; C025279:merocyanine-rhodanine; D012236:Rhodanine