Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018799 (heart disease)
 34,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Gap junctions play essential roles in the normal function of the heart and arteries, mediating the spread of the electrical impulse that stimulates synchronized contraction of the cardiac chambers, and contributing to co-ordination of function between cells of the arterial wall. Altered gap junctional coupling is implicated in the genesis of arrhythmia, a major cause of death in heart disease. Two abnormalities in myocardial gap junctions distribution at the border zone of infarcts and reduced levels of connexin43 (Cx43; alpha 1)--may lead to heterogeneous wavefront propagation and lowered conduction velocity, key factors that precipitate arrhythmia. In the major arteries, endothelial cells express Cx40 (alpha 5) and Cx37 (alpha 4) and, in some instances, also Cx43, whereas underlying medial smooth muscle cells express only Cx43. Increased Cx43 expression between medial smooth muscle cells is intimately linked to phenotypic transformation to the synthetic state in both early human coronary phenotypic transformation to the synthetic state in both early human coronary atherosclerosis, and in the response of the arterial wall to injury. The accumulating evidence suggests that gap junctions in both their guises--as pathways for cell-to-cell signalling in the vessel wall and as pathways for impulse conduction in the heart--may have key roles in the initial pathogenesis and eventual clinical manifestation of human cardiovascular disease.
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PMID:Cardiovascular disease. 1020 5

Atrial fibrillation (AF) appears in the presence or absence of structural heart disease. The majority of foci causing AF are located near the ostia of pulmonary veins (PVs), where cardiomyocytes and vascular smooth muscle cells interdigitate. Connexins (Cx) form gap junction channels and participate in action potential propagation. Genetic variants in genes encoding Cx40 and Cx37 affect their expression or function and may contribute to PV arrhythmogenicity. DNA was obtained from 196 patients with drug-resistant, symptomatic AF with and without structural heart disease, who were referred for percutaneous catheter ablation. Eighty-nine controls were matched for age, gender, hypertension, and BMI. Genotyping of the Cx40 -44G > A, Cx40 +71A > G, Cx40 -26A > G, and Cx37 1019C > T polymorphisms was performed. The promoter A Cx40 polymorphisms (-44G > A and +71A > G) showed no association with non-structural or structural AF. Distribution of the Cx40 promoter B polymorphism (-26A > G) was different in structural AF when compared to controls (p = 0.03). There was no significant difference with non-structural AF (p = 0.50). The distribution of the Cx37 1019C > T polymorphism was different in non-structural AF (p = 0.03) but not in structural AF (p = 0.08) when compared to controls. Our study describes for the first time an association of drug-resistant non-structural heart disease AF with the Cx37 1019C > T gene polymorphism. We also confirmed the association of the Cx40 - 26G > A polymorphism in patients with AF and structural disease.
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PMID:Differential Association of Cx37 and Cx40 Genetic Variants in Atrial Fibrillation with and without Underlying Structural Heart Disease. 2935 Dec 27