Modification of the cardiovascular response of posterior hypothalamic adenosine A2A receptor stimulation by adenylate cyclase and KATP channel blockade in anesthetized rats

The potential role of adenosine signaling in the pathogenesis of melanoma

Melanoma cancer cell proliferation, motility, invasion, and tumor growth is affected by the adenosine pathway that consists of adenosine-synthesizing enzymes, receptors, and their respective agonists/antagonists. Accumulating evidence suggests that ischemia and inflammation, two conditions associated with melanoma, display dysregulated adenosine metabolism, which implicates it as the mechanism responsible for the pathogenesis of melanoma, thereby resulting in advanced diagnosis and therapy. Suppression of adenosine signaling by inhibiting adenosine receptors or adenosine-generating enzymes (CD39 and CD73) on melanoma cells presents a novel therapeutic target for patients with melanoma. This review summarizes the role of adenosine signaling in the pathogenesis of melanoma to advance its understanding and hence improve therapeutics and management.

Therapeutic potential of A2 adenosine receptor pharmacological regulators in the treatment of cardiovascular diseases, recent progress, and prospective

Adenosine and its analogs are of particular interest as potential therapeutic agents for treatment of cardiovascular diseases (CVDs). A2 adenosine receptor subtypes (A2a and A2b) are extensively expressed in cardiovascular system, and modulation of these receptors using A2 adenosine receptor agonists or antagonists regulates heart rate, blood pressure, heart rate variability, and cardiovascular toxicity during both normoxia and hypoxia conditions. Regulation of A2 adenosine receptor signaling via specific and novel pharmacological regulators is a potentially novel therapeutic approach for a better understanding and hence a better management of CVDs. This review summarizes the role of pharmacological A2 adenosine receptor regulators in the pathogenesis of CVDs.

The role of NO in the posterior hypothalamus in amygdala-generated pressor responses in conscious rats

The nitrergic system modulates cardiovascular functions of the central nucleus of amygdala (CeA) and the posterior hypothalamus (PH) which are involved in the central regulation of the cardiovascular system. The aim of this study was to investigate the contribution of nitric oxide (NO) in the PH in eliciting cardiovascular responses produced through electrical stimulation (ES) of the CeA. Rats were implanted with a stimulation electrode and a parenchymal cannula system into the CeA and a parenchymal cannula or a microdialysis probe into the PH. The next day, the femoral artery was cannulated for haemodynamic measurement. The CeA was electrically stimulated to produce cardiovascular response. The nitric oxide synthetase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME; 400 nmol/100 nl) or artificial cerebrospinal fluid were injected into the PH or the CeA before the ES of the CeA. The dialysates were collected from the PH to determine the L-citrulline and the L-glutamic acid levels. L-NAME injection into the CeA but not to the PH suppressed the increases in the mean arterial pressure produced by the ES of the CeA significantly; however, heart rate was not affected by L-NAME injection into either the PH or the CeA. L-citrulline and L-glutamic acid levels in the PH were shown to be increased by the ES of the CeA. NO is involved between the PH and the CeA which has a considerable role in the central regulation of the cardiovascular system.