Participación de los mineralocorticoides en la respuesta inflamatoria vascular asociada a la hipertensión

Abstract

Introduction Besides its physiological role in the control of hydroelectrolyte balance at renal level, aldosterone plays an important role in cardiovascular alterations associated with hypertension, such as left ventricular hypertrophy, cardiac fibrosis, congestive heart failure, etc. The aim of the present study was to evaluate the effect of endogenous mineralocorticoids on vascular inflammation associated with hypertension in rats. Methods Male spontaneously hypertensive rats (SHR) (18 weeks old) were treated with two doses of eplerenone (30 and 100 mg/kg/day) for 10 weeks. A group of (n = 8) untreated SHR was used as a control-vehicle group, and a group of Wistar Kyoto rats (n=8) was used as a reference of normotensive conditions. Aortic mRNA expression and plasma levels of interleukin (IL)-1β, IL-6 and tumour necrosis factor α (TNF-α) were measured. The aortic mRNA expression of the transcription nuclear factor κB (NF-κB) p50 subunit precursor, p105, and its inhibitor (IκB) were also measured. Results SHR showed higher mRNA expression of IL-1β, IL-6 and TNF-α than WKY (p < 0.05) and higher plasma levels of IL-1β and IL-6 than WKY (p < 0.05). SHR also had an increased mRNA expression of NF-κB, and a reduction of I κB. Only the treatment with 100 mg/kg/day eplerenone, significantly reduced SAP. Both doses of the drug reduced plasma levels of IL-1β, IL-6 and aortic mRNA expression of IL-1β, IL-6 and TNF-α to a comparable extent (p < 0.05). In addition, both doses of eplerenone reduced NF-κB mRNA aortic expression and increased IκB mRNA expression in a similar extent (p < 0.05). Conclusions Mineralocorticoids participate in the vascular inflammatory process associated with hypertension in SHR. This effect seems to be mediated by enhanced vascular expression of cytokines through a modification of the NF-κB/IκB system.