Is the regulation of apoptosis altered in smooth muscle cells of adult spontaneously hypertensive rats?

Whereas the protein product of the Bcl-2 gene inhibits apoptosis, the protein product of the Bax gene acts as a promoter of apoptosis. To gain insight into the regulation of apoptosis in vascular smooth muscle cells in arterial hypertension, we investigated the expression of the proteins Bcl-2 and B...

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Detalles Bibliográficos
Autores: Diez-Martinez, J. (Javier)|||/items/4f3a0e43-12bf-403d-9dc7-31fab0d11d41, Panizo, A. (Ángel)|||/items/8528099c-dc2d-4568-9796-db012dbad990, Hernandez, M. (Milagros)|||/items/5038422f-054b-4410-a617-ce777509a41a, Pardo, J. (Javier)|||/items/e4eb259d-28ff-499e-a5d6-cbfb8fae03b8
Tipo de recurso: artículo
Fecha de publicación:1997
País:España
Institución:Universidad de Navarra
Repositorio:Dadun. Depósito Académico Digital de la Universidad de Navarra
Idioma:inglés
OAI Identifier:oai:dadun.unav.edu:10171/20090
Acceso en línea:https://hdl.handle.net/10171/20090
Access Level:acceso abierto
Palabra clave:Apoptosis
Hypertension, arterial
Muscle, smooth, vascular
Descripción
Sumario:Whereas the protein product of the Bcl-2 gene inhibits apoptosis, the protein product of the Bax gene acts as a promoter of apoptosis. To gain insight into the regulation of apoptosis in vascular smooth muscle cells in arterial hypertension, we investigated the expression of the proteins Bcl-2 and Bax in small intramyocardial arteries of 36-week-old normotensive Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR). In addition, 16-week-old SHR were treated for 20 weeks with the angiotensin-converting enzyme inhibitor quinapril and killed at 36 weeks of age. We measured the percentages of smooth muscle cells expressing these proteins using monoclonal antibodies and the avidin-biotin immunoperoxidase method. Compared with WKY, untreated SHR exhibited increased (P<.001) Bcl-2 expression and similar Bax expression. Values of Bcl-2 measured in quinapril-treated SHR were significantly lower than values measured in untreated SHR and similar to values measured in WKY. Quinapril-treated SHR showed higher (P<.001) Bax expression than WKY and untreated SHR. Bcl-2 expression was directly correlated with systolic pressure. Inverse correlations were found between the expression of Bax and the activities of both cardiac and circulating angiotensin-converting enzyme. These findings suggest that smooth muscle cell apoptosis might be inhibited in small arteries of adult SHR as a consequence of an excess of the protein Bcl-2. In addition, our results suggest that chronic angiotensin-converting enzyme inhibition might restore the susceptibility to apoptosis in these cells through stimulation of the protein Bax.