Electrophysiological effects of SN-6, a novel Na+/Ca2+ exchange inhibitor on membrane currents in guinea pig ventricular myocytes. 2007

Chun-Feng Niu, and Yasuhide Watanabe, and Takahiro Iwamoto, and Kanna Yamashita, and Hiroshi Satoh, and Tuyoshi Urushida, and Hideharu Hayashi, and Junko Kimura
Department of Internal Medicine III, Hamamatsu University School of Medicine, 1-20-1 Hondayama, Hamamatsu, Shizuoka, 431-3192, Japan.

We examined the effect of SN-6 on the Na+/Ca2+ exchanger (NCX) current (I(NCX)) and other membrane currents in isolated guinea pig ventricular myocytes using the whole-cell voltage clamp technique. SN-6 suppressed the bidirectional I(NCX) in a concentration-dependent manner. The IC50 values of SN-6 were 2.3 microM and 1.9 microM for the outward and inward components of the bidirectional I(NCX), respectively. On the other hand, SN-6 suppressed the unidirectional outward I(NCX) more potently than the inward I(NCX), with an IC(50) value of 0.6 microM. SN-6 at 10 microM inhibited the unidirectional inward I(NCX) by only 22.4 +/- 3.1%. SN-6 suppressed I(NCX) more potentially when intracellular Na+ concentration became higher. SN-6 inhibited I(Na), I(Ca), I(Kr), I(Ks), and I(K1) by about 13%, 34%, 33%, 18%, and 13%, respectively. SN-6 shortened the action potential duration (APD) by about 34% and 25% at APD(50) and APD(90), respectively. These results indicate that SN-6 inhibits NCX in a similar manner to that of KB-R7943. SN-6 and KB-R7943 inhibit the unidirectional outward I(NCX) more potently than the unidirectional inward I(NCX). Both drugs inhibit NCX in an intracellular Na+ concentration-dependent manner. However, SN-6 affected other membrane currents less potently than KB-R7943.

UI MeSH Term Description Entries
D008564 Membrane Potentials The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization). Resting Potentials,Transmembrane Potentials,Delta Psi,Resting Membrane Potential,Transmembrane Electrical Potential Difference,Transmembrane Potential Difference,Difference, Transmembrane Potential,Differences, Transmembrane Potential,Membrane Potential,Membrane Potential, Resting,Membrane Potentials, Resting,Potential Difference, Transmembrane,Potential Differences, Transmembrane,Potential, Membrane,Potential, Resting,Potential, Transmembrane,Potentials, Membrane,Potentials, Resting,Potentials, Transmembrane,Resting Membrane Potentials,Resting Potential,Transmembrane Potential,Transmembrane Potential Differences
D006168 Guinea Pigs A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research. Cavia,Cavia porcellus,Guinea Pig,Pig, Guinea,Pigs, Guinea
D006352 Heart Ventricles The lower right and left chambers of the heart. The right ventricle pumps venous BLOOD into the LUNGS and the left ventricle pumps oxygenated blood into the systemic arterial circulation. Cardiac Ventricle,Cardiac Ventricles,Heart Ventricle,Left Ventricle,Right Ventricle,Left Ventricles,Right Ventricles,Ventricle, Cardiac,Ventricle, Heart,Ventricle, Left,Ventricle, Right,Ventricles, Cardiac,Ventricles, Heart,Ventricles, Left,Ventricles, Right
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia
D001593 Benzyl Compounds Benzene derivatives that contain a benzyl group with the general formula Phenyl-CH2-R. Compounds, Benzyl
D016276 Ventricular Function The hemodynamic and electrophysiological action of the HEART VENTRICLES. Function, Ventricular,Functions, Ventricular,Ventricular Functions
D053778 Thiazolidines Reduced (protonated) form of THIAZOLES. They can be oxidized to THIAZOLIDINEDIONES. Thiazolidine
D019831 Sodium-Calcium Exchanger An electrogenic ion exchange protein that maintains a steady level of calcium by removing an amount of calcium equal to that which enters the cells. It is widely distributed in most excitable membranes, including the brain and heart. Ca(2+)-Na(+) Exchanger,Calcium-Sodium Carrier,Calcium-Sodium Exchanger,Na(+)-Ca(2+) Exchanger,Sodium-Calcium Carrier,Ca(2+)-Na(+) Antiporter,Calcium-Sodium Antiporter,Na(+)-Ca(2+) Antiporter,Sodium-Calcium Antiporter,Antiporter, Calcium-Sodium,Antiporter, Sodium-Calcium,Calcium Sodium Antiporter,Calcium Sodium Carrier,Calcium Sodium Exchanger,Carrier, Calcium-Sodium,Carrier, Sodium-Calcium,Exchanger, Calcium-Sodium,Exchanger, Sodium-Calcium,Sodium Calcium Antiporter,Sodium Calcium Carrier,Sodium Calcium Exchanger

Related Publications

Chun-Feng Niu, and Yasuhide Watanabe, and Takahiro Iwamoto, and Kanna Yamashita, and Hiroshi Satoh, and Tuyoshi Urushida, and Hideharu Hayashi, and Junko Kimura
March 1998, Zhongguo yao li xue bao = Acta pharmacologica Sinica,
Chun-Feng Niu, and Yasuhide Watanabe, and Takahiro Iwamoto, and Kanna Yamashita, and Hiroshi Satoh, and Tuyoshi Urushida, and Hideharu Hayashi, and Junko Kimura
November 2016, Naunyn-Schmiedeberg's archives of pharmacology,
Chun-Feng Niu, and Yasuhide Watanabe, and Takahiro Iwamoto, and Kanna Yamashita, and Hiroshi Satoh, and Tuyoshi Urushida, and Hideharu Hayashi, and Junko Kimura
May 1994, The Journal of physiology,
Chun-Feng Niu, and Yasuhide Watanabe, and Takahiro Iwamoto, and Kanna Yamashita, and Hiroshi Satoh, and Tuyoshi Urushida, and Hideharu Hayashi, and Junko Kimura
December 2000, The Journal of physiology,
Chun-Feng Niu, and Yasuhide Watanabe, and Takahiro Iwamoto, and Kanna Yamashita, and Hiroshi Satoh, and Tuyoshi Urushida, and Hideharu Hayashi, and Junko Kimura
December 2000, The Journal of physiology,
Chun-Feng Niu, and Yasuhide Watanabe, and Takahiro Iwamoto, and Kanna Yamashita, and Hiroshi Satoh, and Tuyoshi Urushida, and Hideharu Hayashi, and Junko Kimura
November 1988, European journal of pharmacology,
Chun-Feng Niu, and Yasuhide Watanabe, and Takahiro Iwamoto, and Kanna Yamashita, and Hiroshi Satoh, and Tuyoshi Urushida, and Hideharu Hayashi, and Junko Kimura
January 2001, Yao xue xue bao = Acta pharmaceutica Sinica,
Chun-Feng Niu, and Yasuhide Watanabe, and Takahiro Iwamoto, and Kanna Yamashita, and Hiroshi Satoh, and Tuyoshi Urushida, and Hideharu Hayashi, and Junko Kimura
December 2002, The Journal of physiology,
Chun-Feng Niu, and Yasuhide Watanabe, and Takahiro Iwamoto, and Kanna Yamashita, and Hiroshi Satoh, and Tuyoshi Urushida, and Hideharu Hayashi, and Junko Kimura
March 2007, Annals of the New York Academy of Sciences,
Chun-Feng Niu, and Yasuhide Watanabe, and Takahiro Iwamoto, and Kanna Yamashita, and Hiroshi Satoh, and Tuyoshi Urushida, and Hideharu Hayashi, and Junko Kimura
March 1999, Japanese journal of pharmacology,
Copied contents to your clipboard!