Changes in Inward Rectifier K+ Channels in Hepatic Stellate Cells During Primary Culture.
10.3349/ymj.2008.49.3.459
- Author:
Dong Hyeon LEE
1
;
In Deok KONG
;
Joong Woo LEE
;
Kyu Sang PARK
Author Information
1. Department of Physiology, College of Medicine, Pochon CHA University, Seongnam, Gyeonggi-do, Korea. qsang@yonsei.ac.kr
- Publication Type:Original Article
- Keywords:
Hepatic stellate cells;
inward rectifier K+ channels;
electrophysiology;
real-time RT-PCR
- MeSH:
Animals;
Barium/pharmacology;
Blotting, Western;
Cells, Cultured;
Electrophysiology;
Liver/cytology/*metabolism;
Male;
Membrane Potentials/drug effects;
Potassium/pharmacology;
Potassium Channels, Inwardly Rectifying/genetics/metabolism/*physiology;
Rats;
Rats, Sprague-Dawley;
Reverse Transcriptase Polymerase Chain Reaction
- From:Yonsei Medical Journal
2008;49(3):459-471
- CountryRepublic of Korea
- Language:English
-
Abstract:
PURPOSE: This study examined the expression and function of inward rectifier K+ channels in cultured rat hepatic stellate cells (HSC). MATERIALS AND METHODS: The expression of inward rectifier K+ channels was measured using real-time RT-PCR, and electrophysiological properties were determined using the gramicidin-perforated patch-clamp technique. RESULTS: The dominant inward rectifier K+ channel subtypes were K(ir)2.1 and K(ir)6.1. These dominant K+ channel subtypes decreased significantly during the primary culture throughout activation process. HSC can be classified into two subgroups: one with an inward-rectifying K+ current (type 1) and the other without (type 2). The inward current was blocked by Ba2+ (100micrometer) and enhanced by high K+ (140mM), more prominently in type 1 HSC. There was a correlation between the amplitude of the Ba2+-sensitive current and the membrane potential. In addition, Ba2+ (300micrometer) depolarized the membrane potential. After the culture period, the amplitude of the inward current decreased and the membrane potential became depolarized. CONCLUSION: HSC express inward rectifier K+ channels, which physiologically regulate membrane potential and decrease during the activation process. These results will potentially help determine properties of the inward rectifier K+ channels in HSC as well as their roles in the activation process.