title: The feasibility and limitation of patch-clamp recordings from neonatal rat cardiac ventricular slices.
abstract: Examine the feasibility of whole-cell patch-clamp recordings from the cardiac ventricular slices of newborn (P(3)-P(7)) Sprague-Dawley rats to identify a better substitute for single cardiac myocytes prepared using enzymatic treatment. High resistance seals (>1 GΏ) were obtained from cardiac ventricle tissues prepared without using enzymatic treatment. Thereafter, cell-attached and whole-cell patch-clamp techniques were used on thin cardiac slices (200 μm thick) in 2009 in the Institute of Molecular Medicine of Peking University. An averaged sodium current (n=11 cells) was recorded in the cell-attached mode, and this displayed features similar to those previously reported for isolated rat ventricular myocytes. The outward potassium current, hyperpolarization-activated cation channel or I (f) channel (HCN channel), and action potential were recorded in the whole-cell mode (n=2 cells), and the identical properties were observed from the cardiac slices. The cell-attached mode is stable and reliable for recording the ion current. The resting potential for cardiac slices measured using current-clamp recording in the whole-cell mode was -50 to -70 mV. The resting potential of cardiac slices has properties similar to those of enzyme-prepared cardiomyocytes, with the exception that it is positive. We achieved whole-cell patch-clamp recordings from cardiac slices and affirmed the feasibility and values of both cell-attached and whole-cell recording modes using this technique. Nevertheless, there remain difficulties and limitations associated with the application of whole-cell patch-clamping to cardiac slices, due primarily to the existence of large amounts of connective tissue even in newborn rats.
authors.affiliation: Department of Cardiology, Shanghai Sixth People's Hospital, Shanghai Jiaotong University, Shanghai 200233, China. Huangdong1004@126.com
authors.forename: Dong
authors.initials: D
authors.lastname: Huang
authors.forename: Jingbo
authors.initials: J
authors.lastname: Li
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D000831:Animals, Newborn; D054815:Cyclic Nucleotide-Gated Cation Channels / Q000378:metabolism; D006352:Heart Ventricles / Q000378:metabolism*; D064428:Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels; D018408:Patch-Clamp Techniques / Q000379:methods*; D011188:Potassium / Q000378:metabolism; D015221:Potassium Channels / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012964:Sodium / Q000378:metabolism
chemical_list: D054815:Cyclic Nucleotide-Gated Cation Channels; D064428:Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels; D015221:Potassium Channels; D012964:Sodium; D011188:Potassium