Adenosine A_1, A_(2a), A_(2b), and A_3 Receptors in Hematopoiesis. 2. Expression of Receptor mRNA in Resting and Lipopolysaccharide-Activated Mouse RAW 264.7 Macrophages

摘要

Expression of mRNA for adenosine receptor subtypes A_1, A_(2a), A_(2b), and A_3 in normal and lipopolysaccharide (LPS)-activated murine RAW 264.7 macrophages has been investigated using the method of quantitative real-time polymerase chain reaction. The results have shown a very low, unquantifiable expression of adenosine A1 receptor mRNA in both normal and LPS-activated macrophages. The other three adenosine receptor mRNAs have been found to be expressed at various but always quantifiable levels. Activation of the macrophages by LPS induced upregulation of the expression of adenosine receptor A_(2a) and A_(2b) mRNA, whereas the expression of adenosine receptor A_3 mRNA was downregulated. Unstimulated macrophages exhibited a high expression of the A_(2b) adenosine receptor mRNA. The findings are discussed from the point of view of the antiinflammatory and hematopoiesis-stimulating roles of the adenosine receptor signaling.