The effect of different doses (1-50 µ M) of imipramine (IMI) and desipramine (DES) on the rate and force of contraction of isolated rat atria was studied. IMI and DES produced a dose-dependent increase in force of contraction (31- 94% for IMI and 35-118% for DES). Pretreatment of rats with reserpine (5 mg/kg) on the isolated atria with propranolol (1 µ g) inhibited the positive ionotropic eff...

The influence of adenosine receptor agonists and antagonists on cocaine-and amphetamine-induced hyperactivity was examined in mice. All adenosine receptor agonists significantly decreased the locomotor activity in mice, and the effects were dose-dependent. It seems that adenosine A1 and A2 receptors might be involved in this reaction. Moreover, all adenosine receptor agonists: 2-p-(2-carboxyeth...

Rheumatoid arthritis is one of the most important chronic, progressive and disabling inflammatory diseases characterized by joint destructive process associated with synovial proliferation and secretion of high levels of proinflammatory mediators including cytokines and growth factors. Early diagnosis and effective therapy are crucial in order to prevent unfavorable outcome with joint deteriora...

Because hypoxia increases extracellular adenosine levels and stimulates angiogenesis, we evaluated the relative roles of reduced oxygen concentrations and adenosine receptor activation in the production of angiogenic factors. In vitro, we analyzed the effects of hypoxia and adenosine on the secretion of angiogenic factors from human microvascular endothelial cells (HMEC-1). To study the effects...

We have previously demonstrated that adenosine plus homocysteine enhanced endothelial basal barrier function and protected against agonist-induced barrier dysfunction in vitro through attenuation of RhoA activation by inhibition of isoprenylcysteine-O-carboxyl methyltransferase. In the current study, we tested the effect of elevated adenosine on pulmonary endothelial barrier function in vitro a...

We and others have shown that adenosine, acting at its receptors, is a potent modulator of inflammation and angiogenesis. To better understand the regulation of adenosine receptors during these processes we studied the effects of IL-1, TNF-alpha, and IFN-gamma on expression and function of adenosine receptors and select members of their coupling G proteins in human dermal microvascular endothel...

In the 10 years since our previous International Union of Basic and Clinical Pharmacology report on the nomenclature and classification of adenosine receptors, no developments have led to major changes in the recommendations. However, there have been so many other developments that an update is needed. The fact that the structure of one of the adenosine receptors has recently been solved has al...

The interaction between the neuromodulator adenosine and adenosine receptors on the surface of neurons modifies the neurons’ responses to neurotransmitters. The activated adenosine receptors alter the levels of small signaling molecules (i.e., second messengers) in the cells. Depending on the receptors and cells involved, these changes can make it easier or more difficult for neurotransmitters ...

Human peripheral blood monocytes have been found to undergo a transitory state of high accessory activity before they fully become macrophages. Time kinetics were done to follow this accessory potential. Studying the regulation of accessory activity, we have found that monocyte derived accessory cells (m-AC) pass through two phases of development, both of which are adversely controlled by ...