Abstract:
:Anisotropic impulse conduction was studied in neonatal rat heart cell monolayers produced by culturing cells on a growth-directing substrate of collagen. Monolayers consisting of parallel-oriented cells without visible intercellular clefts were selected for experiments; cell lengths and widths were 65.8 +/- 12.5 and 12.2 +/- 3.2 microns (n = 49), respectively. Action potential upstrokes were measured by using 12 photodiodes selected within a 10x10 diode array and a voltage-sensitive dye (RH-237). The size of the area sensed by a single diode was 14 x 14 microns. High-density multiple recordings (resolution, up to 15 microns) demonstrated the variability of local activation delays and of the maximal rate of rise of the action potential upstroke (Vmax), which are presumably related to the microscopic cellular architecture. Mean macroscopic conduction velocities measured over distances of 135 microns were 34.6 +/- 4.5 and 19.0 +/- 4.3 cm/s (mean +/- SD, n = 13, P < .0001) in longitudinal and transverse directions, respectively. The anisotropic velocity ratio was 1.89 +/- 0.38 (n = 13). Mean Vmax was not significantly different in two directions (122.0 +/- 17.4 V/s longitudinally versus 125.2 +/- 15.6 V/s transversely, n = 13, P = NS). In conclusion, we developed an anisotropic cell culture model suitable for studying impulse conduction with cellular resolution. The anisotropic velocity ratio was close to values measured in vivo. By contrast, Vmax was not dependent on the direction of propagation.
journal_name
Circ Resjournal_title
Circulation researchauthors
Fast VG,Kléber AGdoi
10.1161/01.res.75.3.591subject
Has Abstractpub_date
1994-09-01 00:00:00pages
591-5issue
3eissn
0009-7330issn
1524-4571journal_volume
75pub_type
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更新日期:2003-02-07 00:00:00
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更新日期:2004-06-11 00:00:00
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更新日期:1991-02-01 00:00:00
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更新日期:1992-01-01 00:00:00
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更新日期:2002-07-26 00:00:00
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更新日期:1989-07-01 00:00:00
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更新日期:1987-09-01 00:00:00
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pub_type: 杂志文章,评审
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更新日期:2013-08-30 00:00:00
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pub_type: 杂志文章
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更新日期:2001-11-09 00:00:00
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更新日期:2010-07-23 00:00:00