N6-cyclopentyladenosine inhibits proliferation of murine haematopoietic progenitor cells in vivo.

Effects of N6-cyclopentyladenosine (CPA), the selective adenosine A1 receptor agonist, on bone marrow haematopoietic progenitor cells for granulocytes and macrophages (CFC-GM) were investigated by utilizing the model of haematopoietic damage induced by 5-fluorouracil. Experiments were performed in vivo on B10CBAF1 mice. A single i.

Effects of stable adenosine receptor agonists on bone marrow hematopoietic cells as inferred from the cytotoxic action of 5-fluorouracil.

The aim of the study was to investigate the effects of stable adenosine receptor agonists on bone marrow hematopoiesis by utilizing the model of hematopoietic damage induced by 5-fluorouracil (5-FU), a cycle-specific cytotoxic agent. Effects of a non-selective agonist NECA activating all the known adenosine receptors (A1, A2A, A2B, A3) and of the selective agonists for A1 (CPA), A2A (CGS 21680), and A3 (IB-MECA) adenosine receptors were investigated. Experiments were performed with B10CBAF1 mice under in vivo conditions.

Hemopoiesis-stimulating action of adamantylamide dipeptide: kinetics of increase of GM-CFC in femur and co-stimulating activity of serum, role of bone marrow stromal cells.

Chief part of hemopoietic stromal cells in mediating hemopoiesis-stimulating effects of adamantylamide dipeptide (AdDP), a synthetic immunomodulatory compound, has been determined in a series of combined in vivo/in vitro studies. Indirect stimulatory effect of AdDP on proliferation of hemopoietic progenitor cells for granulocytes and macrophages (GM-CFC) was proved to be mediated by the cells of hemopoietic microenvironment growing as adherent stromal cell populations in vitro. These results supplement previously reported findings of a positive role which is played by AdDP at modulating the interplay among stimulatory cytokines and their cellular sources, and are in consent with the idea to introduce AdDP as a constituent of the hemopoiesis- and immunity-stimulating supportive medical care.

Combination of drugs elevating extracellular adenosine with granulocyte colony-stimulating factor promotes granulopoietic recovery in the murine bone marrow after 5-fluorouracil treatment.

Combined administration of drugs elevating extracellular adenosine, namely dipyridamole and adenosine monophosphate, together with granulocyte colony-stimulating factor was shown to enhance granulopoietic recovery in the bone marrow of mice treated with 5-fluorouracil. Enhanced regeneration was found both at the level of hematopoietic progenitor cells for granulocytes and macrophages and in the compartment of morphologically recognizable granulocyte precursors. The results might have positive clinical impact.

Influence of the joint treatment with granulocyte colony-stimulating factor and drugs elevating extracellular adenosine on erythropoietic recovery following 5-fluorouracil-induced haematotoxicity in mice.

The presented data address the problem of pleiotropic effects of granulocyte colony-stimulating factor (G-CSF) and suggest the ability of drugs increasing the level of extracellular adenosine to activate erythropoiesis when given jointly with G-CSF. To demonstrate these interactions, the effects of the drugs on the recovery from erythropoietic damage induced in mice by a single dose of 5-fluorouracil (5-FU) were investigated. Elevation of extracellular adenosine and thus activation of adenosine receptors was induced by joint administration of dipyridamole (DP), a drug inhibiting the cellular uptake of adenosine, and adenosine monophosphate (AMP), an adenosine prodrug.