ISSN:0263-6352    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

The renin–angiotensin system (RAS) plays a pivotal role in the regulation of fluid, electrolyte balance and blood pressure, and is a modulator of cellular growth and proliferation. Biological actions of RAS are linked to the binding of the effector molecule, angiotensin II (AngII), to specific membrane receptors, mostly the AT1subtype and, to a lesser extent, other subtypes. Following the identification and characterization of the AT2subtype receptor, it has been proposed that a complex interaction between AngII and its receptors may play an important role in the effects of RAS. In this paper current information on AngII subtype receptors – their structure, regulation and intracellular signalling – are reviewed, with a particular emphasis on the potential relevance for cardiovascular pathophysiology. In addition, we discuss modulation of expression of the AT2receptor and its interaction with the AT1receptor subtype, as well as the potential effects of this receptor on blood pressure regulation. A better understanding of the integrated effects of the AngII subtype receptors may help to elucidate the function of the RAS, as well as their participation in the mechanisms of cardiovascular disease and attendant therapeutic implications.

ISSN:0263-6352    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0263-6352    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0263-6352    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0263-6352    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0263-6352    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0263-6352    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0263-6352    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0263-6352    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background and objectivesPlasma leptin levels have been shown to be an independent risk factor for cardiovascular disease. Leptin has been shown to have sympathetic and vascular effects, and may increase cardiovascular risk through increased blood pressure, left ventricular hypertrophy, or atherosclerotic mechanisms. This study examines whether leptin levels, independent of body mass and insulin resistance, are a risk factor for hypertension and left ventricular hypertrophy.Methods and participantsA population-based, cross-sectional sample of 410 adults from rural Spain was studied. The correlations between plasma leptin levels and left ventricular mass index, sum of wall thicknesses, and blood pressure were calculated. Multiple linear regression analysis was used to adjust for other cardiovascular risk factors.ResultsAfter adjusting for age, body mass index, systolic blood pressure, sex, and insulin resistance, leptin was inversely associated with left ventricular mass index (β = −0.20,P<0.01). Leptin was also inversely related to the sum of wall thicknesses; however, this association did not reach statistical significance (β = −0.12,P= 0.063). Leptin was not statistically associated with blood pressure after adjusting for body mass index.ConclusionsThe results do not support the hypothesis that leptin increases cardiovascular risk by increasing left ventricular mass index or blood pressure. Other mechanisms, related to atherosclerosis, could explain the increased risk of cardiovascular diseases observed with high leptin levels.

ISSN:0263-6352    

出版商:OVID    

年代:2003

数据来源: OVID