Purinoceptors in renal microvessels: adenosine-activated and cytochrome P450 monooxygenase-derived arachidonate metabolites.
Journal Title: Pharmacological Reports - Year 2005, Vol 57, Issue
Abstract
Cytochrome P450 (CYP)-dependent epoxyeicosatrienoic acids (EETs) dilaterat preglomerular microvessels (PGMVs) when adenosine 2A receptors (A(2A)R) are stimulated. As high salt intake increases epoxygenase activity and adenosine levels, we hypothesized that renal adenosine responses would be greater in high salt-fed rats. We have obtained evidence supporting this hypothesis in rats fed a high salt diet for 7 days. Stimulation of adenosine receptors with 2-chloroadenosine in kidneys obtained from rats on high salt (4%) intake produced an increase in EET release that was several-fold greater than in kidneys of rats on normal salt (0.4% NaCl) diets, which was associated with a sharp decline in renovascular resistance. Under conditions of high salt intake, an associated upregulation of A(2A)R and 2C23 protein expression was observed. As EETs are renal vasodilator and natriuretic eicosanoids, the antipressor response to salt loading may operate through an A(2A)R - EET mechanism. These findings expand the role of adenosine-related mechanisms in protecting renal function.
Authors and Affiliations
M A Carroll, Monica Cheng, Elvira Liclican, Jing Li, Anabel Doumad, John McGiff
Influence of amlodipine and atenolol on lipopolysaccharide (LPS)-induced serum concentrations of TNF-alpha, IL-1beta, IL-6 in spontaneously hypertensive rats (SHR).
An increasing body of evidence suggests that cytokines may play a role in the pathogenesis of cardiovascular diseases. Immunopharmacological studies provide new information on immunomodulating activity of some drugs, inc...
Low-dose oral caffeine induces a specific form of behavioral sensitization in rats.
The present study assessed the effects of a low dose of orally administered caffeine on sensitization of open-field behavior in rats. Rats had free access to untreated water every day or water containing 0.2 mg/ml of caf...
Enhancement of fibrinolysis by gel-filtered platelets and its quenching by cytochalasin B and GPIIb/IIIa antagonists.
The effects of gel-filtered platelets on euglobulin clot lysis time (ECLT) were analyzed to elucidate the possible role of platelets in thrombolysis. Gel-filtered platelet-supplemented ECLT (plt-ECLT) was significantly s...
Involvement of NMDA receptors in the antidepressant-like action of adenosine.
Background and Method: In this work, the contribution of NMDA receptors to the antidepressant-like effect of adenosine in the forced swimming test (FST) was investigated. Results: The pretreatment of mice with NMDA or D-...
Effect of HMG-CoA (3-hydroxy-3-methylglutaryl-CoA) reductase inhibitors on the concentration of insulin-like growth factor-1 (IGF-1) in hypercholesterolemic patients.
Studies have shown that HMG-CoA reductase inhibitors (statins) play an important role in the prevention and treatment of atherosclerosis and hyperlipidemia. The aim of this study was to investigate the effect of 3-month...