Activation of mineralocorticoid receptors by exogenous glucocorticoids and the development of cardiovascular inflammatory responses in adrenalectomized rats

Activation of the mineralocorticoid receptor (MR) in the context of a high salt intake produces cardiovascular inflammation plus cardiac fibrosis and failure. Inactivation of vascular 11beta-hydroxysteroid dehydrogenase type 2 activity in intact animals by carbenoxolone (CBX) produces a similar pathology, presumably reflecting coronary vascular MR activation by endogenous glucocorticoids. To test this hypothesis, we have used adrenalectomized rats, without endogenous corticosteroids, and examined the consequences of corticosterone (CORT) replacement on a series of cardiovascular disease parameters. Uninephrectomized adrenalectomized Sprague Dawley rats given 1% NaCl/0.3% KCl to drink were treated for 8 d as follows: control; 20 mg deoxycorticosterone (DOC); 2 mg/d CORT; 2.5 mg/d CBX; CORT plus CBX (CORT/CBX); and CORT/CBX plus 100 mg/kg.d eplerenone. Markers of cardiac oxidative stress (p22(phox) and NOX4 mRNA) were up-regulated in the DOC and CORT/CBX groups; in contrast, inflammatory cell infiltration was increased and endothelial nitric oxide synthase down-regulated by CORT as well as by DOC and CORT/CBX. In the kidney, connective tissue growth factor mRNA levels were increased by DOC and CORT/CBX; in contrast, DOC had no effect on mRNA levels for channel inducing factor or endothelin 3, which were elevated only by CORT/CBX. All changes noted were reversed by eplerenone. Rats given 10-fold lower CORT (0.2 mg/d) with or without CBX showed no change in any parameter. These results suggest that there exist distinct but overlapping ligand-specific MR-mediated tissue responses to a classic mineralocorticoid (DOC) and to the glucocorticoid CORT, in the presence and absence of CBX to block vascular 11beta-hydroxysteroid dehydrogenase type 2.

Medienart:

E-Artikel

Erscheinungsjahr:

2010

Erschienen:

2010

Enthalten in:

Zur Gesamtaufnahme - volume:151

Enthalten in:

Endocrinology - 151(2010), 6 vom: 06. Juni, Seite 2622-8

Sprache:

Englisch

Beteiligte Personen:

Young, Morag J [VerfasserIn]
Morgan, James [VerfasserIn]
Brolin, Kim [VerfasserIn]
Fuller, Peter J [VerfasserIn]
Funder, John W [VerfasserIn]

Links:

Volltext

Themen:

Cyba protein, rat
EC 1.14.13.39
EC 1.6.3.-
EC 1.6.3.1
Glucocorticoids
Journal Article
Mineralocorticoids
NADPH Oxidase 4
NADPH Oxidases
Nitric Oxide Synthase Type III
Nox4 protein, rat
Receptors, Glucocorticoid
Receptors, Mineralocorticoid
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 30.06.2010

Date Revised 08.05.2020

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1210/en.2009-1476

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM197520944