Faculty Collaboration Database

Delayed rectification in single cells isolated from guinea pig sinoatrial node. Am J Physiol 1992 Mar;262(3 Pt 2):H921-5

Date

03/01/1992

Pubmed ID

1558202

DOI

10.1152/ajpheart.1992.262.3.H921

Scopus ID

2-s2.0-0026524968 (requires institutional sign-in at Scopus site)   63 Citations

Abstract

We have studied delayed rectifier K+ currents (IK) in cells isolated from the sinoatrial node (SAN) region of the guinea pig. Using whole cell patch-clamp procedures, we measured the voltage dependence of IK activation and IK kinetics and the IK equilibrium potential in 4.8 mM extracellular K concentration solutions. Experiments were designed to contrast properties of guinea pig SAN IK with those of IK recorded from SAN cells of the rabbit. We find that guinea pig SAN IK differs from IK recorded from single rabbit SAN cells in its activation threshold, and in the absence of inactivation of whole cell currents recorded over a wide voltage range. These results, along with the relative insensitivity of guinea pig SAN IK to E-4031 and lanthanum, suggest that under our experimental conditions, a strongly rectifying IK component (IK,r) is not the major component of delayed rectification in the guinea pig SAN, as it appears to be in SAN cells of the rabbit.

Author List

Anumonwo JM, Freeman LC, Kwok WM, Kass RS

Author

Wai-Meng Kwok PhD Professor in the Anesthesiology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Anti-Arrhythmia Agents
Electrophysiology
Guinea Pigs
In Vitro Techniques
Lanthanum
Membrane Potentials
Piperidines
Potassium
Potassium Channels
Pyridines
Sinoatrial Node