Search results for "adenosine receptor"

Induction of Apoptosis in Rat Cardiocytes by A3 Adenosine Receptor Activation and Its Suppression by Isoproterenol

2000

The purpose of the present study was to investigate the mechanisms involved in the induction of apoptosis in newborn cultured cardiomyocytes by activation of adenosine (ADO) A3 receptors and to examine the protective effects of beta-adrenoceptors. The selective agonist for A3 ADO receptors Cl-IB-MECA (2-chloro-N6-iodobenzyl-5-N-methylcarboxamidoadenosine) and the antagonist MRS1523 (5-propyl-2-ethyl-4-propyl-3-(ethylsulfanylcarbonyl)-6-phenylpy rid ine-5-carboxylate) were used. High concentrations of the Cl-IB-MECA (or = 10 microM) agonist induced morphological modifications of myogenic cells, such as rounding and retraction of cell body and dissolution of contractile filaments, followed by…

Stimulation of Wound Revascularization by Adenosine Receptor Activation

2010

Adenosine is an endogenous mediator implicated in wound healing. The exact mechanisms and receptors involved are still under evaluation. We have observed that topical application of a selective adenosine A2A receptor agonist promotes wound healing in experimental animals, both healthy and with impaired healing. Histological analysis revealed that adenosine promoted granulation tissue formation, with increased cellularity, matrix deposition, and vessel density. Adenosine may exert effects on many different cell types that finally result in promotion of angiogenesis and, furthermore, homing of endothelial precursor cells into sites of injury. We will review the effect of adenosine receptor ac…

Evidence that adenosine is not involved in the non-adrenergic non-cholinergic relaxation in the rat duodenum.

1990

In rat isolated duodenal segments, adenosine induced, in the presence of atropine and guanethidine, a dose-dependent, long-lasting (about 20 s), tetrodotoxin (TTX)-resistant relaxation both in endoluminal pressure and in isometric tension. Electrical field stimulation (EFS) induced, in the presence of atropine and guanethidine, a TTX-sensitive short-lasting (about 6 s) relaxation followed by a sustained rebound contraction. Theophylline, a P1 receptor antagonist, at the concentration of 100 microM caused a marked inhibition of the adenosine-induced relaxation, while the EFS-induced relaxation was not modified. Our results suggest that adenosine induces relaxation of the rat duodenal smooth …

Nitroglycerin-induced cardioprotection is endothelial nitric oxide synthase- dependent

2015

Purpose We sought to evaluate the contribution of the endogenous NO pathway to the cardioprotective action of nitroglycerin (NTG). Methods and Results Anesthetized rabbits were subjected to 30-min myocardial ischemia (isc) and 3-h reperfusion (rep) and randomized into: Control group (no further intervention); PostC group (application of 8 cycles 30-sec isc/rep) and NTG treated group (2 μg/kg-1/min-1 IV bolus) for 65 min starting 10 min prior to rep. In additional groups, pharmacological inhibitors of NOS, nNOS, iNOS, PI3K, adenosine receptors and PKG were administrated with or without NTG. The infarcted (I) to risk (R) ratio was estimated. In a second experimental series tissue samples were…

The electrophysiology of adenosine in the mammalian central nervous system

1991

MODELLING STUDIES ON MOLECULAR PATHWAYS RELATED TO HYPOXIA IN SOLID TUMOR GROWTH

2011

P1086 : Complex effects of adenosine receptor antagonists in models of liver fibrosis

2015

Guanosine-Mediated Anxiolytic-Like Effect: Interplay with Adenosine A1 and A2A Receptors

2020

Acute or chronic administration of guanosine (GUO) induces anxiolytic-like effects, for which the adenosine (ADO) system involvement has been postulated yet without a direct experimental evidence. Thus, we aimed to investigate whether adenosine receptors (ARs) are involved in the GUO-mediated anxiolytic-like effect, evaluated by three anxiety-related paradigms in rats. First, we confirmed that acute treatment with GUO exerts an anxiolytic-like effect. Subsequently, we investigated the effects of pretreatment with ADO or A1R (CPA, CCPA) or A2AR (CGS21680) agonists 10 min prior to GUO on a GUO-induced anxiolytic-like effect. All the combined treatments blocked the GUO anxiolytic-like effect, …

Endogenous adenosine inhibits hippocampal CA1 neurones: further evidence from extra- and intracellular recording.

1988

Extracellular and intracellular recordings from CA1 pyramidal neurones of rats in vitro were used to study the effects of endogenous and exogenously applied adenosine. The adenosine receptor antagonist, caffeine, enhanced the intracellular recorded e.p.s.p.-i.p.s.p. sequence evoked by stimulation of the stratum radiatum which is antagonized by exogenous adenosine. The late, potassium dependent i.p.s.p. was not antagonized. The adenosine uptake inhibitor, nitrobenzylthioinosine (NBTI), mimicked the effects of exogenously applied adenosine. The effects of NBTI and of exogenously applied adenosine were antagonized by caffeine in the same manner. Exposure to adenosine deaminase enhanced the evo…

A1 receptors mediate adenosine inhibitory effects in mouse ileum via activation of potassium channels.

2008

Abstract Aims We investigated the effects induced by exogenous adenosine on the spontaneous contractile activity of the longitudinal muscle of a mouse ileum, the receptor subtypes activated, the involvement of enteric nerves and whether opening of K + channels was a downstream event leading to the observed effects. Main methods Mechanical responses of the mouse ileal longitudinal muscle to adenosine were examined in vitro as changes in isometric tension. Key findings Adenosine caused a concentration-dependent reduction of the spontaneous contraction amplitude of the ileal longitudinal muscle up to its complete disappearance. This effect induced was markedly reduced by an A 1 receptor antago…