Cardiac Ca current does not run down and is very sensitive to isoprenaline in the nystatin-method of whole cell recording.

Autor: Kurachi, Yoshihisa, Asano, Yukio, Takikawa, Reiko, Sugimoto, Tsuneaki
Zdroj: Naunyn-Schmiedeberg's Archives of Pharmacology; 1989, Vol. 340 Issue 2, p219-222, 4p
Abstrakt: The conventional l type Ca channel current (I) was measured in single atrial and ventricular myocytes, with a new whole-cell recording technique using an ionophore, nystatin. The membrane of a cell-attached patch was gradually permeabilized by nystatin (100-200 gg/ml), added to the pipette solution, within 2-5 min after formation of a GΩ-seal. The electrical activity of the cells was measured through the pipette. I, measured with the nystatin-whole cell recording technique, did not exhibit the so-called 'run-down' phenomenon for up to 90 min. The response of I to isoprenaline was also well preserved during the measurement. The half maximal concentration for the isoprenaline-induced increase of I was 8.2 × 10 M, which is a much smaller value than that reported previously. Thus, the nystatin-whole cell clamp recording is a useful technique to measure membrane currents of cardiac myocytes with preserving the physiological intracellular milieu. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index
Externí odkaz: