| Conservation of L-type Ca2+ current characteristics in endo- and epicardial myocytes from rat left ventricle with pressure-induced hypertrophy. | |
| | |
MedLine Citation:
|
PMID: 11810209 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Cardiac hypertrophy alters the regional distribution of action potential duration by affecting the magnitude and kinetics of underlying ionic currents. In the present study, the effect of pressure-induced cardiac hypertrophy on the magnitude and kinetics of the L-type Ca2+ current ( I(CaL)) was investigated in endo- and epicardial myocytes of the rat left ventricular free wall. Cardiac hypertrophy was induced by stenosis of the ascending aorta (AS), which led to a pressure difference between the left ventricular peak pressure and the peripheral systolic blood pressure of 84+/-6 mmHg ( n=5, P<0.0001). Sham-operated animals served as controls ( n=7). I(CaL) was investigated using the whole-cell patch-clamp technique. The magnitude of I(CaL) as well as its inactivation, steady-state activation, steady-state inactivation and recovery from inactivation were similar in endo- and epicardial myocytes of sham-operated rats. In myocytes isolated from AS animals, I(CaL) magnitude was significantly greater than in sham-operated animals (2407+/-127 pA, n=42 versus 1904+/-102 pA, n=33; P<0.01). This difference disappeared, however, when I(CaL) was normalized to cell capacitance. The kinetic properties of I(CaL) were unaffected by AS in both endo- and epicardial myocytes. In conclusion, in pressure-induced cardiac hypertrophy the density and kinetics of I(CaL) are preserved. This suggests that an additional insertion or recruitment of channels normally underlying I(CaL) into the cell membrane compensates for the increased cell size associated with hypertrophy. |
| | |
Authors:
|
Tilmann Volk; Heimo Ehmke |
Related Documents
:
|
12658189 - Effects of acute left ventricular unloading on right ventricular function in normal and... 16970269 - High-dose norepinephrine induces disruption of myocardial extracellular matrix and left... 9809929 - Coupled systolic-ventricular and vascular stiffening with age: implications for pressur... 755029 - The effect of contrast media on the isolated perfused canine heart. 3997289 - Short-term hemodynamic effects of diatrizoate and ioxaglate contrast media in left vent... 2297829 - Relation of left ventricular hemodynamic load and contractile performance to left ventr... 8712359 - Laser-excited atomic fluorescence spectrometry in a pressure-controlled electrothermal ... 1468349 - Averaged steady-state visual evoked cortical potentials at artificially raised intraocu... 3763259 - A comparison of proximal and distal high-frequency jet ventilation in an experimental a... |
Publication Detail:
|
Type: Journal Article Date: 2001-10-09 |
Journal Detail:
|
Title: Pflügers Archiv : European journal of physiology Volume: 443 ISSN: 0031-6768 ISO Abbreviation: Pflugers Arch. Publication Date: 2002 Jan |
Date Detail:
|
Created Date: 2002-01-25 Completed Date: 2002-04-24 Revised Date: 2008-11-21 |
Medline Journal Info:
|
Nlm Unique ID: 0154720 Medline TA: Pflugers Arch Country: Germany |
Other Details:
|
Languages: eng Pagination: 399-404 Citation Subset: IM |
Affiliation:
|
Institut für Physiologie, Universität Hamburg, Hamburg, Germany. volk@uke.uni-hamburg.de |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Animals Aorta / pathology Aortic Valve Stenosis / pathology Blood Pressure / physiology Calcium / metabolism Calcium Channels, L-Type / physiology* Endocardium / pathology Female Heart Ventricles / pathology, physiopathology Hypertrophy, Left Ventricular / pathology, physiopathology* Muscle Fibers, Skeletal / pathology, physiology* Pericardium / pathology Rats Rats, Sprague-Dawley Sarcoplasmic Reticulum / metabolism Ventricular Pressure / physiology |
| Chemical | |
Reg. No./Substance:
|
0/Calcium Channels, L-Type; 7440-70-2/Calcium |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Involvement of GTP-binding protein in pancreatic cAMP-mediated exocytosis.
Next Document: Inhibitory effect of somatostatin on secretin-induced augmentation of the slowly activating K+ curre...