Thesis supervisor: Norbert László Jost
Web address (URL): http://phcol.szote.u-szeged.hu/index_a.htm Location of studies (in Hungarian): Univ. Szeged, Faculty of Medicine, Department of Pharmacology and Pharmacotherapy Abbreviation of location of studies: ÁOK
Description of the research topic:
The postgraduate doctoral theme is included in the field of cardiovascular research and especially of cardiac electrophysiology. We aim to study by applying electrophysiological tools (standard microlelectrode and patch-clamp technique) the role of several transmembrane currents in the action potential repolarization in healthy and special diseased models (as atrial fibrillation and heart failure). We focus on the pharmacological modulation of these diseases in isolated mammalian cardiomyocytes and transgenic expression (cloned cell lines) systems as well.
The patch-clamp technique
Experiments are carried out in freshly enzimatically isolated ventricular myocytes isolated from dog, rabbit and guinea pig hearts. One drop of cell suspension is placed within a transparent recording chamber mounted on the stage of an inverted microscope (Olympus IX 51 or Nikon TMS), and individual myocytes are allowed to settle and adhere to the chamber bottom for at least 5 minutes before superfusion is initiated. Only rod shape cells with clear striations are used. Cell capacitance is measured by applying 10 mV hyperpolarising pulse from –10 mV. The holding potential was -90 mV. The capacity is measured by integration of the capacitive transient divided by the amplitude of the voltage step (10 mV). HEPES buffered Tyrode's solution serves as the normal superfusate. Patch-clamp micropipettes are fabricated from glass capillaries using a microprocessor controlled P-97 Flaming/Brown micropipette puller. These electrodes have resistances between 1.5 and 2.5 Mohms when filled with pipette solution. Membrane currents are recorded with an Axopatch-1D and 200B amplifiers (Axon Instruments, Foster City, CA, USA) using the whole-cell configuration of the patch-clamp technique (see figure). After establishing a high (1-10 Gohm) resistance seal by gentle suction, the cell membrane beneath the tip of the electrode is disrupted by suction or by application of 1.5 V electrical pulses for 1-5 ms. The series resistance is typically 4-8 Mohm before compensation (50-80%, depending on the voltage protocolsMembrane currents are digitized using a 333 kHz analog-to-digital converter (Digidata 1200, Axon Instruments) under software control (pClamp 8.0, Axon Instruments). Analyses are performed using Axon (pClamp 8.0) software after low-pass filtering at 1 kHz. All patch-clamp data are collected at 37 °C.
Required language skills: English Further requirements: TDK munka
Number of students who can be accepted: 1
Deadline for application: 2016-08-31
2024. IV. 17. ODT ülés Az ODT következő ülésére 2024. június 14-én, pénteken 10.00 órakor kerül sor a Semmelweis Egyetem Szenátusi termében (Bp. Üllői út 26. I. emelet).
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