Ultra-short agonist application. A novel approach for the kinetic study of ion channel.

AUZMENDI, JERÓNIMO; FERNÁNDEZ DO PORTO, DARÍO; MOFFATT, LUCIANO

Huerta Grande, Córdoba

Congreso; XXVI Congreso Anual SAN; 2011

The determination of kinetic-molecular mechanisms of ligand-gated ion channels depends on the ability to apply agonist to outside-out patch clamp preparations. Thus, to ensure ultra-fast applications (20μs) that may resolve partial activation states, it is necessary to minimized practical variables that limit the temporal resolution in the agonist application. The solution exchange system is controlled by a piezo that moves the interface between two dual streams solutions on the patch pipette. Mechanical vibrations caused by increasing the velocity of the piezo result in spurious applications of agonist. In this study, we apply an optimization method based on Fourier transformations that allowed us to damp oscillations and obtain a transfer function. Thus, we obtain pulses with a t50 of 26.3 ± 1.08μs (n =150) when the initial command was a square pulse of 20μs. Furthermore, we evaluated performance pulse and found 92.54 ± 1.31% (n =150) crossing through the interface. In this way, we show that it is possible to solve the most important limitation for ultra-fast applications of agonists and thus we have a novel tool for analyzing the kinetics data.