A transient voltage-dependent outward current in cultured cerebellar granules. Issue 4 (August 1989)

• Record Type: Journal Article
• Authors: Robello, Mauro; Carignani, Corrado; Marchetti, Carla
• Is Part Of: Bioscience reports. Volume 9:Issue 4(1989)
• Page Start: 451
• Page End: 457
• Publication Date: 1989-08
• Subjects: cerebellar granule cell cultures -- potassium currents -- patch-clamp technique; Molecular biology -- Periodicals; Cytology -- Periodicals; 572.8
• DOI: 10.1007/BF01117047
• Languages: English
• ISSNs: 0144-8463

Abstract

Abstract : Granule cells were dissociated from rat cerebella with a procedure that yields a 98% pure cell population. Potassium currents in these cells were studied using the patch-clamp technique. Depolarizing pulses of 10 mV step and 100 ms duration from a holding potential of −80 mV elicited two different potassium outward currents: a transient, low-voltage activated component and a long lasting, high-voltage activated component. At +30 mV, the total current reached an amplitude of 2 nA (mean value of 15 experiments). The reversal potential of the transient current, estimated by measuring tail currents, was −77 mV, close to that predicted by the Nernst equation. The transient current was half inactivated with a holding potential of −78 mV and completely inactivated with −50 mV or more positive holding potentials. Finally, the current decay could be fitted by the sum of two exponentials with time constants of about 20 and 250 ms.