Pacemaker Mechanism of Porcine Sino-atrial Node Cells(PACEMAKER CELLS IN THE HEART AND GUT)
スポンサーリンク
概要
- 論文の詳細を見る
In cardiac sino-atrial node (SAN) cells, time- and voltage-dependent changes in the gating of various ionic currents provide spontaneous, stable and repetitive firing of action potentials. To address the ionic nature of the species-dependent heart rate, action potentials and membrane currents were recorded in single cells dissociated from the porcine SAN, and compared with those from SAN cells of rabbits, guinea-pigs and mice. The porcine SAN cells exhibited spontaneous activity with a frequency of 60-80 min^<-1>, which was much slower than that of rabbit SAN cells. Under voltage clamp conditions, depolarization activated the L-type Ca^<2+> current (I_<CaL>) followed by a gradual activation of the delayed rectifier K^+ current (I_K) while hyperpolarization activated the hyperpolarization-activated cation current (I_h). It was found that the major component of I_K in porcine SAN is the slowly activating I_K (I_<Ks>) , in contrast to SAN cells of the rabbit and other species in which the rapid I_K (I_<Kr>) plays an active role in repolarization and the subsequent pacemaker depolarization. Replacement of rabbit I_<Kr> with porcine I_<Ks> and a slight modification in the gating parameters and amplitudes of other current systems in the 'Kyoto Model' gave an adequate reconstruction of spontaneous action potentials as well as of the voltage clamp recordings. We conclude that the density and the kinetics of I_K contribute, in part, to the different heart rates of various species.
- 日本平滑筋学会の論文
著者
-
ONO Kyoichi
Department of Pharmacology, Akita University School of Medicine
-
SHIBATA Shigehiro
Department of Critical Care Medicine, Iwate Medical University
-
IIJIMA Toshihiko
Department of Pharmacology, Akita University School of Medicine
-
Shibata Shigehiro
Department Of Anesthesiology Akita City Hospital
-
Ono Kyoichi
Department Of Pharmacology Akita University School Of Medicine
-
Ono Kyoichi
Dep. Of Pharmacology Akita Univ. School Of Medicine
-
Iijima Toshihiko
Dep. Of Pharmacology Akita Univ. School Of Medicine
-
Iijima Toshihiko
Department Of Life And Medicine Urayasu Hospital Of Juntendo University School Of Medicine
-
Ono Kyoichi
Department Of Cell Physiology Akita University Graduate School Of Medicine
-
Shibata Shigehiro
Department of Anesthesiology, Akita City Hospital
関連論文
- Role of Individual Ionic Current Systems in the SA Node Hypothesized by a Model Study
- Role of Individual Ionic Current Systems in Ventricular Cells Hypothesized by a Model Study
- A prospective cohort study of ALI/ARDS in the Tohoku district of Japan (second report)
- The Pathological Role of Transient Receptor Potential Channels in Heart Disease
- Molecular and Electrical Remodeling of L- and T-Type Ca^ Channels in Rat Right Atrium With Monocrotaline-Induced Pulmonary Hypertension(Arrhythmia/Electrophysiology)
- Molecular and Electrical Remodeling of L- and T-Type Ca2+ Channels in Rat Right Atrium With Monocrotaline-Induced Pulmonary Hypertension
- On the Inotropic Actions of Arginine Vasopressin in Ventricular Muscle of the Guinea Pig Heart
- Soluble adhesion molecules and cytokines in septic acute lung injury patients
- Analgesic action of loperamide, an opioid agonist, and its blocking action on voltage-dependent Ca^ channels
- Modulation by Mibefradil of the Histamine-Induced Ca^ Entry in Human Aortic Endothelial Cells
- Pathophysiological Significance of T-type Ca^ Channels : Preface
- Pathophysiological Significance of T-type Ca^ Channels : Properties and Functional Roles of T-type Ca^ Channels in Cardiac Pacemaking
- Sevoflurane Inhibition of the Slowly Activating Delayed Rectifier K^+ Current in Guinea Pig Ventricular Cells
- Pacemaker Mechanism of Porcine Sino-atrial Node Cells(PACEMAKER CELLS IN THE HEART AND GUT)
- Cloning and Functional Expression of a Novel Splice Variant of Rat TRPC4
- Cloning and Functional Expression of a Novel Splice Variant of Rat TRPC4
- Suppressive effects of sivelestat on interleukin 8 and TNF-α production from LPS-stimulated granulocytes in whole blood culture
- Efficacy of Metformin in Non-Obese Type 2 Diabetic Patients with Secondary Failure to Sulfonylurea Therapy
- Use of the bispectral index during the early postresuscitative phase after out-of-hospital cardiac arrest
- Nitrous oxide administration during washout of sevoflurane improves postanesthetic agitation in children
- DECREASES IN ARTERIAL PRESSURE AND HEART RATE ELICITED BY ELECTRICAL STIMULATION OF THE ANTERIOR HYPOTHALAMUS OF PENTOBARBITAL ANESTHETIZED DOGS
- DEPRESSION BY CARBACHOL OF CALCIUM-DEPENDENT ACTION POTENTIALS IN THE CANINE VENTRICULAR MUSCLE DEPOLARIZED BY POTASSIUM
- EFFECTS ON ATRIO-VENTRICULAR CONDUCTION OF PROPRANOLOL, PINDOLOL AND CARTEOLOL IN THE DOG HEART IN SITU AS ASSESSED BY AUTOMATED DEVICES
- Direct Effects of Esmolol and Landiolol on Cardiac Function, Coronary Vasoactivity, and Ventricular Electrophysiology in Guinea-Pig Hearts
- AGE- RELATED CHANGES IN ELECTROPHYSIOLOGICAL PROPERTIES CBA/N MICE UTRICULAR TYPE II HAIR CELLS
- DOWN-REGULATION OF L-TYPE CA2+ CURRENT IN LEFT ATRIAL MYOCYTES OF RATS DURING EXPERIMENTAL CARDIAC HYPERTROPHY
- Interleukin-18 levels reflect the long-term prognosis of acute lung injury and acute respiratory distress syndrome
- Differential effects of isoproterenol on the canine atrial action potential in the presence of carbachol or nicorandil.
- Voltage- and use-dependent block of the inward calcium current by MCI-176, a new non-dihydropyridine calcium antagonist, in canine ventricular muscles and single ventricular cells of the guinea-pig.
- Sevoflurane Inhibition of the Slowly Activating Delayed Rectifier K+ Current in Guinea Pig Ventricular Cells
- Changes in membrane potentials and currents of ventricular cells of the guinea pig heart by a new cardiotonic drug, MCI-154.
- Effect of adenine on twitch and other contractile responses of single fibers of amphibian fast skeletal muscle.
- Postnatal Changes in mRNA Expression of the K+ Channel in Rat Cardiac Ventricles.