Data/hora: 11/06/2024 04:12:45

Provedor de dados: | Brazilian Journal of Medical and Biological Research
País: | Brazil
Título: | Hypotrophy of conduit artery walls of the offspring of nitric oxide-defective rats
Autores: | Kristek,F.; Gerová,M.
Data: | 2004-04-01
Ano: | 2004
Palavras-chave: | Artery; Nitric oxide; Offspring; Hypertension; Vascular smooth muscle; Extracellular matrix; Morphometry.
Resumo: | The objective of the present study was to investigate the structure of the arterial walls of the offspring stemming from nitric oxide (NO)-defective hypertensive parents. The parents were treated with N G-nitro-L-arginine methyl ester (40 mg kg-1 day-1) for 5 weeks. Blood pressure was measured noninvasively in six 30-day-old rats and nine age-matched controls. The cardiovascular system was perfused with glutaraldehyde at 120 mmHg. The thoracic aorta and carotid artery were processed for electron microscopy, and geometry was determined by light microscopy. Endothelial cells, smooth muscle cells (SMC) and extracellular matrix (ECM) were determined by the point counting method in electron micrographs of the carotid artery. The blood pressure of experimental offspring was 150.0 ± 2.3 vs 104.6 ± 2.1 mmHg (P &lt; 0.01) for the controls and their heart/body weight ratio of 3.9 ± 0.1 vs 4.4 ± 0.2 (P &lt; 0.05) for the controls indicated cardiac hypotrophy. The wall thickness (tunica intima and media) of the thoracic aorta and carotid artery of experimental offspring was decreased to 78.9% (P &lt; 0.01) and 83.8% (P &lt; 0.01), respectively, compared to controls, as confirmed by a respective cross-sectional area of 85.3% (P &lt; 0.01) and 84.1% (P &lt; 0.01). The wall thickness/inner diameter ratio was reduced to 75% (P &lt; 0.01) in the thoracic artery and to 81.5% (P &lt; 0.01) in the carotid artery. No change in endothelial cell volume density or ECM was observed in the tunica intima of the carotid artery, and SMC volume density was lower in the tunica media (37.6 ± 0.9 vs 44.7 ± 1.1% for controls, P &lt; 0.01), indicating compromised SMC development. Interference with arginine metabolism, a decrease in NO, and other factors are possible mechanisms underlying the structural alterations of the cardiovascular system of offspring from NO-defective hypertensive rats.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2004000400018
Editor: | Associação Brasileira de Divulgação Científica
Relação: | 10.1590/S0100-879X2004000400018
Formato: | text/html
Fonte: | Brazilian Journal of Medical and Biological Research  v.37 n.4 2004
Fonte: | info:eu-repo/semantics/openAccess