Potassium currents in periglomerular cells of frog olfactory bulb in vitro.
Voltage-activated currents have been recorded from periglomerular cells in thin slices of frog olfactory bulb. Cells were examined with whole-cell patch clamp methods. The voltage-dependent potassium currents were studied after pharmacological block of inward currents. Depolarising steps from -130 mV gave an early transient, A-type, outward current and a delayed rectifier K+ current (IKV). The two currents could be isolated on the basis of the differences in their kinetic properties. The A-current developed following a third-order kinetics when the membrane was depolarised to potentials more positive than -40 mV after preconditioning to potentials more negative than -60 mV. Once activated (tau a 2.5 ms at 0 mV), IA inactivated following a single exponential (tau ha about 60 ms). IKV activated with a second-order kinetics above -30 mV with a time constant of 4 ms at 0 mV. IA and IKV were sensitive, respectively, to 4-aminopyridine (4-AP) and tetraethylammonium (TEA).
Bardoni
R
R
Puopolo
M
M
Magherini
P C
PC
Belluzzi
O
O
D015761:4-Aminopyridine / Q000494:pharmacology; D000818:Animals; D001001:Anura; D002104:Cadmium / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D066298:In Vitro Techniques; D007395:Interneurons / Q000737:chemistry* / Q000502:physiology; D008564:Membrane Potentials / Q000502:physiology; D009830:Olfactory Bulb / Q000166:cytology / Q000502:physiology*; D018408:Patch-Clamp Techniques; D011188:Potassium / Q000378:metabolism / Q000494:pharmacology; D026902:Potassium Channel Blockers; D015221:Potassium Channels / Q000502:physiology*; D019789:Tetraethylammonium; D013757:Tetraethylammonium Compounds / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology
D026902:Potassium Channel Blockers; D015221:Potassium Channels; D013757:Tetraethylammonium Compounds; D002104:Cadmium; D013779:Tetrodotoxin; D019789:Tetraethylammonium; D015761:4-Aminopyridine; D011188:Potassium; D002118:Calcium