Properties of K+ currents recorded from cultured ovine trachea submucosal gland cells.
We have used the whole cell recording technique to investigate voltage-activated outward currents in cultured ovine trachea submucosal gland cells. The cultured gland cells secreted lysozyme in response to secretagogues, methacholine (20 microM), phenylephrine (100 microM) and substance P (10 microM). Most cells in culture for 7-21 days expressed a voltage-activated outward current at potentials positive to -30 mV. This outward current inactivated slowly, by 44 +/- 6% during a 3 sec depolarization to +30 mV. The voltage-activated outward current was sensitive to the potassium channel inhibitors tetraethylammonium bromide (5 mM), 4-aminopyridine (500 microM) and glibenclamide (1 microM). These data suggest that the outward voltage-activated currents observed are due to K+ channel activity. In cells with little or no outward current present the potassium channel opener Ro 31-6930 produced an additional voltage-activated net outward current. This effect of Ro 31-6930 was sensitive to glibenclamide (1 microM). Our results suggest that some cultured submucosal gland cells express voltage-activated K+ currents with a mixed pharmacology to antagonists and that a portion of this current is sensitive to modulation by Ro 31-6930.
Griffin
A
A
Department of Physiology, St. George's Hospital Medical School, London, UK.
Scott
R H
RH
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D001578:Benzopyrans / Q000494:pharmacology; D002118:Calcium / Q000502:physiology; D002478:Cells, Cultured; D004553:Electric Conductivity; D006706:Homeostasis; D009092:Mucous Membrane / Q000166:cytology / Q000502:physiology; D011188:Potassium / Q000502:physiology*; D026902:Potassium Channel Blockers; D011725:Pyridines / Q000494:pharmacology; D012704:Serous Membrane / Q000166:cytology / Q000502:physiology; D012756:Sheep; D014132:Trachea / Q000166:cytology / Q000502:physiology*
D001578:Benzopyrans; D026902:Potassium Channel Blockers; D011725:Pyridines; C062764:Ro 31-6930; D000255:Adenosine Triphosphate; D011188:Potassium; D002118:Calcium