scholarly journals Ischemia Impairs the Association Between Connexin 43 and M3 Subtype of Acetylcholine Muscarinic Receptor (M3-mAChR) in Ventricular Myocytes

2006 ◽  
Vol 17 (3-4) ◽  
pp. 129-136 ◽  
Author(s):  
Peng Yue ◽  
Yong Zhang ◽  
Zhimin Du ◽  
Jing Xiao ◽  
Zhenwei Pan ◽  
...  
Keyword(s):  
Muscarinic Receptor ◽  
Connexin 43 ◽  
Ventricular Myocytes ◽  
M3 Subtype

scholarly journals Hypoxia causes connexin 43 internalization in neonatal rat ventricular myocytes

2010 ◽  
Vol 29 (3) ◽  
pp. 222-233 ◽  
Author(s):  
A. Danon ◽  
N. Zeevi-Levin ◽  
D. Pinkovich ◽  
T. Michaeli ◽  
A. Berkovich ◽  
...  
Keyword(s):  
Connexin 43 ◽  
Ventricular Myocytes ◽  
Neonatal Rat ◽  
Rat Ventricular Myocytes ◽  
Neonatal Rat Ventricular Myocytes

Altered beta-adrenergic and muscarinic response of CFTR Cl- current in dialyzed cardiac myocytes

1995 ◽  
Vol 268 (5) ◽  
pp. H1795-H1802
Author(s):  
S. I. Zakharov ◽  
R. D. Harvey
Keyword(s):  
Patch Clamp ◽  
Muscarinic Receptor ◽  
Ventricular Myocytes ◽  
Receptor Activation ◽  
Current Response ◽  
Patch Clamp Technique ◽  
Beta Adrenergic ◽  
Perforated Patch ◽  
Clamp Technique ◽  
Perforated Patch Clamp

Autonomic regulation of the cardiac cystic fibrosis transmembrane conductance regulator (CFTR) Cl- current was studied in isolated guinea pig ventricular myocytes using various configurations of the whole cell patch-clamp technique. When currents were recorded using the conventional patch-clamp technique, it was possible to continue to activate the Cl- current on repeated exposure to isoproterenol (Iso) for up to 60 min after initiating dialysis. However, there was significant rundown of the magnitude of the Cl- current response to the maximally stimulating concentrations of Iso. In addition, the concentration of Iso that produced half-maximal activation of the Cl- current (K1/2) increased with time. Conversely, the K1/2 for acetylcholine inhibition of the Iso-activated current decreased with time. When currents were recorded using the perforated patch-clamp technique, the sensitivity to both beta-adrenergic- and muscarinic-receptor stimulation was stable. Immediately after initiation of dialysis with the conventional patch-clamp technique, the sensitivity to Iso was nearly identical to that determined using the perforated patch-clamp technique. However, the initial sensitivity to muscarinic-receptor activation was significantly greater. These results indicate that cell dialysis associated with conventional patch-clamp techniques not only results in a time-dependent rundown of current amplitude, but it also significantly alters the concentration dependence of beta-adrenergic and muscarinic-receptor regulation of ion channel function.

scholarly journals The Role of T-Tubule Organization in Regulation of Intracellular Ca2+ Handling by Muscarinic Receptor Stimulation in Ventricular Myocytes

2021 ◽  
Vol 120 (3) ◽  
pp. 238a
Author(s):  
Andriy E. Belevych ◽  
Vladimir Bogdanov ◽  
Dmitry A. Terentyev ◽  
Sandor Gyorke
Keyword(s):  
Muscarinic Receptor ◽  
Ventricular Myocytes ◽  
Receptor Stimulation

Muscarinic receptor subtypes in canine trachea

1990 ◽  
Vol 258 (6) ◽  
pp. L349-L354 ◽  
Author(s):  
J. F. Brichant ◽  
D. O. Warner ◽  
S. J. Gunst ◽  
K. Rehder
Keyword(s):  
Electric Field ◽  
Muscarinic Receptor ◽  
Contractile Response ◽  
Receptor Subtypes ◽  
Field Stimulation ◽  
Muscarinic Receptor Subtypes ◽  
Electric Field Stimulation ◽  
M3 Receptors ◽  
M3 Subtype

Prejunctional and postjunctional muscarinic receptor subtypes were characterized in canine trachealis muscle strips. In vitro contractile responses of muscle strips to acetylcholine or electric field stimulation were determined in the absence and the presence of gallamine, pirenzepine, and 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP). Gallamine had no effect on the contractile response to acetylcholine but enhanced the contractile response to electric field stimulation. Pirenzepine and 4-DAMP reduced the contractile response to acetylcholine and electric field stimulation. The pA2 value for pirenzepine vs. acetylcholine [7.18 +/- 0.59 (SD)] was consistent with the affinity of pirenzepine for M2 or M3-receptors; whereas the pA2 value for 4-DAMP vs. acetylcholine (8.92 +/- 0.42) and the extremely low affinity of gallamine indicated postjunctional muscarinic receptors of the M3 subtype. The enhancement of the contractile response to electric field stimulation by gallamine suggested the presence of M2-prejunctional receptors.

The muscarinic receptor gene expressed in rabbit parietal cells is the m3 subtype

1992 ◽  
Vol 103 (3) ◽  
pp. 870-875 ◽  
Author(s):  
Masayoshi Kajimura ◽  
Michael A. Reuben ◽  
George Sachs
Keyword(s):  
Muscarinic Receptor ◽  
Receptor Gene ◽  
Parietal Cells ◽  
M3 Subtype

scholarly journals Acute Detubulation of Ventricular Myocytes Amplifies the Inhibitory Effect of Cholinergic Agonist on Intracellular Ca2+ Transients

2021 ◽  
Vol 12 ◽  
Author(s):  
Andriy E. Belevych ◽  
Vladimir Bogdanov ◽  
Dmitry A. Terentyev ◽  
Sandor Gyorke
Keyword(s):  
Muscarinic Receptor ◽  
Cardiac Myocytes ◽  
Muscarinic Receptors ◽  
Parasympathetic Nervous System ◽  
Ventricular Myocytes ◽  
Heart Function ◽  
Critical Role ◽  
Inhibitory Effect ◽  
Intracellular Ca ◽  
Image Pixels

Muscarinic receptors expressed in cardiac myocytes play a critical role in the regulation of heart function by the parasympathetic nervous system. How the structural organization of cardiac myocytes affects the regulation of Ca2+ handling by muscarinic receptors is not well-defined. Using confocal Ca2+ imaging, patch-clamp techniques, and immunocytochemistry, the relationship between t-tubule density and cholinergic regulation of intracellular Ca2+ in normal murine ventricular myocytes and myocytes with acute disruption of the t-tubule system caused by formamide treatment was studied. The inhibitory effect of muscarinic receptor agonist carbachol (CCh, 10 μM) on the amplitude of Ca2+ transients, evoked by field-stimulation in the presence of 100 nM isoproterenol (Iso), a β-adrenergic agonist, was directly proportional to the level of myocyte detubulation. The timing of the maximal rate of fluorescence increase of fluo-4, a Ca2+-sensitive dye, was used to classify image pixels into the regions functionally coupled or uncoupled to the sarcolemmal Ca2+ influx (ICa). CCh decreased the fraction of coupled regions and suppressed Ca2+ propagation from sarcolemma inside the cell. Formamide treatment reduced ICa density and decreased sarcoplasmic reticulum (SR) Ca2+ content. CCh did not change SR Ca2+ content in Iso-stimulated control and formamide-treated myocytes. CCh inhibited peak ICa recorded in the presence of Iso by ∼20% in both the control and detubulated myocytes. Reducing ICa amplitude up to 40% by changing the voltage step levels from 0 to –25 mV decreased Ca2+ transients in formamide-treated but not in control myocytes in the presence of Iso. CCh inhibited CaMKII activity, whereas CaMKII inhibition with KN93 mimicked the effect of CCh on Ca2+ transients in formamide-treated myocytes. It was concluded that the downregulation of t-tubules coupled with the diminished efficiency of excitation–contraction coupling, increases the sensitivity of Ca2+ release and propagation to muscarinic receptor-mediated inhibition of both ICa and CaMKII activity.

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