Transient outward potassium current in rabbit atrium is depressed after short-time rapid atrial pacing but recovers after a longer pacing period

Rok, strany: 2008, 174 - 178

In rabbit, after short-time rapid atrial pacing (RAP), atrial ion currents are reduced similarly as in human chronic atrial fibrillation (AF). Using the rabbit model, time-course of transient outward potassium current (Ito) remodeling due to RAP was studied. RAP (600 bpm) was applied via an atrial lead for 0 (control), 24 and 120 h, n = 4 animals/group. Using patch clamp technique in whole-cell mode, current densities and biophysical properties were measured in isolated atrial myocytes. After 24 h of RAP, a reduction of peak Ito (mean ± SEM, test potential +50 mV, +37°C) was observed (60.3 ± 5.4 pA/pF (control, n = 20) vs. 28.0 ± 2.5 pA/pF (24 h, n = 21)). Inactivation of Ito was slower after 24 h, other biophysical properties were unaltered. However, Ito recovered after 120 h: 51.7 ± 4.5 pA/pF (n = 26, p = n.s. vs. control). Inactivation tended to also recover to initial values but was still different to control. Early Ito remodeling due to RAP in rabbits seems to be more complex than previously thought: a time course of Ito remodeling with swayings has to be considered when using the rabbit model of RAP in order to study early remodeling or rather its therapeutic manipulation.

ISO 690:

Laszlo, R., Eick, C., Schwiebert, M., Schreiner, B., Weig, H., Weretka, S., Schreieck, J. 2008. Transient outward potassium current in rabbit atrium is depressed after short-time rapid atrial pacing but recovers after a longer pacing period. In General Physiology and Biophysics, vol. 27, no.3, pp. 174-178. 0231-5882.

APA:

Laszlo, R., Eick, C., Schwiebert, M., Schreiner, B., Weig, H., Weretka, S., Schreieck, J. (2008). Transient outward potassium current in rabbit atrium is depressed after short-time rapid atrial pacing but recovers after a longer pacing period. General Physiology and Biophysics, 27(3), 174-178. 0231-5882.