Abstract:
:Electrotonic coupling of cardiac myocytes at gap junctions may influence patterns of conduction in myocardium. To delineate the three-dimensional structure and distribution of intercellular junctions, we analyzed serial ultrathin sections of canine myocardium with transmission electron microscopy and disaggregated myocytes with scanning electron microscopy. Morphometric analysis of left ventricular myocardium sectioned in three orthogonal planes revealed that 80% of total gap junctional membrane occurred in large, ribbon-like gap junctions oriented transversely at cell end processes. The remaining 20% of gap junctional membrane was contained in small gap junctions located within plicate segments (interdigitating regions of cell-to-cell adhesion) of intercalated disks. In serial ultrathin sections, all gap junctions were contiguous with plicate segments. Thus, true "lateral" gap junctions do not exist in working ventricular myocytes and would not likely be able to withstand shear forces created by laterally sliding cells. Examination of serial plastic sections with light microscopy revealed complex overlapping of myocytes such that individual myocytes were connected at intercalated disks to an average of 9.1 +/- 2.2 other myocytes. These observations provide an improved understanding of the extent and distribution of cell junctions and should facilitate experimental and model studies of conduction in myocardium.
journal_name
Circ Resjournal_title
Circulation researchauthors
Hoyt RH,Cohen ML,Saffitz JEdoi
10.1161/01.res.64.3.563subject
Has Abstractpub_date
1989-03-01 00:00:00pages
563-74issue
3eissn
0009-7330issn
1524-4571journal_volume
64pub_type
杂志文章abstract::C-reactive protein (CRP), a characteristic inflammatory marker, is a powerful predictor of cardiovascular events. Recent data suggest that CRP may also promote atherogenesis through inducing endothelial dysfunction. Lectin-like oxidized low-density lipoprotein (oxLDL) receptor-1 (LOX-1) is a newly identified endotheli...
journal_title:Circulation research
pub_type: 杂志文章
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更新日期:2004-10-29 00:00:00
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更新日期:1991-03-01 00:00:00
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更新日期:2016-11-11 00:00:00
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pub_type: 杂志文章
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更新日期:2014-08-15 00:00:00
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pub_type: 杂志文章
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更新日期:2016-04-15 00:00:00
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pub_type: 杂志文章,评审
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更新日期:2011-01-07 00:00:00
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pub_type: 杂志文章
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更新日期:1989-11-01 00:00:00
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pub_type: 杂志文章
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更新日期:2008-07-03 00:00:00
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更新日期:1978-03-01 00:00:00
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journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/hh1201.093270
更新日期:2001-06-22 00:00:00
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pub_type: 杂志文章
doi:10.1161/01.RES.0000253900.66640.34
更新日期:2007-01-05 00:00:00
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pub_type: 杂志文章
doi:10.1161/01.RES.0000181132.11393.18
更新日期:2005-09-02 00:00:00
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journal_title:Circulation research
pub_type: 杂志文章
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更新日期:1998-09-07 00:00:00
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journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.65.6.1547
更新日期:1989-12-01 00:00:00
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pub_type: 杂志文章,收录出版
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更新日期:1981-02-01 00:00:00
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journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.79.1.128
更新日期:1996-07-01 00:00:00
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journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.109.206631
更新日期:2010-03-05 00:00:00
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pub_type: 杂志文章
doi:10.1161/01.res.38.2.115
更新日期:1976-02-01 00:00:00
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pub_type: 杂志文章,评审
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更新日期:2007-09-28 00:00:00
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pub_type: 杂志文章,评审
doi:10.1161/CIRCRESAHA.108.171488
更新日期:2008-05-09 00:00:00
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pub_type: 杂志文章,收录出版
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更新日期:1995-07-01 00:00:00
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journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.109.200311
更新日期:2009-07-17 00:00:00
abstract::Cardiovascular aging is associated with decreased endothelial vasoreactivity and prolonged diastolic relaxation. As diminished NO signaling contributes to age-associated endothelial dysfunction, we tested the hypothesis that impaired NO signaling or bioactivity also contributes to slowed ventricular relaxation with ag...
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pub_type: 杂志文章
doi:10.1161/01.res.88.1.97
更新日期:2001-01-19 00:00:00
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journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.0000028007.91385.ee
更新日期:2002-07-26 00:00:00
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journal_title:Circulation research
pub_type: 杂志文章,评审
doi:10.1161/CIRCRESAHA.115.306883
更新日期:2016-05-27 00:00:00
abstract::It has been proposed that lipopolysaccharide (LPS) bound to the 60-kD LPS binding protein (LBP) forms an LPS/LBP complex that, in turn, binds to the CD14 receptor on monocytes/macrophages and stimulates the release of cytokines. We examined the role of LBP and CD14 in tumor necrosis factor-alpha (TNF-alpha) production...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.73.1.15
更新日期:1993-07-01 00:00:00
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journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/hh2301.100817
更新日期:2001-11-23 00:00:00
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journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.64.6.1127
更新日期:1989-06-01 00:00:00
abstract:RATIONALE:Previous studies on the relationship between diabetes and arterial stiffness were mostly cross-sectional. A few longitudinal studies focused on one single direction. Whether the association between arterial stiffness and diabetes is bidirectional remains unclear to date. OBJECTIVE:To explore the temporal rel...
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pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.120.317950
更新日期:2020-12-04 00:00:00