Adenosine inhibits leukocyte-induced vasoconstriction.
Polymorphonuclear leukocytes (PMNs) can induce endothelium-dependent constriction of vascular rings. Because adenosine inhibits the function of PMNs, we examined the effects of adenosine on the PMN-induced coronary vasoconstriction. We measured changes in the isometric tension of isolated rings of canine coronary arteries suspended in an organ chamber filled with Krebs-Henseleit solution after the addition of autologous PMNs. N-formyl-L-methionyl-leucyl-phenylalanine (FMLP)-stimulated PMNs increased the tension of the coronary artery with the endothelium in a concentration-dependent manner. Treatment of FMLP-stimulated PMNs with adenosine inhibited both the adhesion of PMNs to the endothelium and the PMN-induced vasoconstriction. Stimulation of PMNs with CGS-21680C, but not with cyclohexyladenosine, inhibited both the adhesion of PMNs to the endothelium and the PMN-induced vasoconstriction. However, treatment of coronary arteries with adenosine had no effect on the adherence of PMNs to the endothelium and the PMN-induced constriction. These results suggest that stimulation of adenosine A2a receptors on PMNs may inhibit the PMN-induced vasoconstriction by inhibiting the adhesion of PMNs to the endothelium.
Minamino
T
T
First Department of Medicine, Osaka University School of Medicine, Japan.
Kitakaze
M
M
Node
K
K
Funaya
H
H
Inoue
M
M
Hori
M
M
Kamada
T
T
D000241:Adenosine / Q000494:pharmacology*; D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D003331:Coronary Vessels / Q000187:drug effects / Q000502:physiology; D004285:Dogs; D004730:Endothelium, Vascular / Q000502:physiology; D005260:Female; D066298:In Vitro Techniques; D007962:Leukocytes / Q000502:physiology*; D008297:Male; D009504:Neutrophils / Q000187:drug effects / Q000502:physiology; D014661:Vasoconstriction / Q000187:drug effects* / Q000502:physiology*; D014665:Vasodilator Agents / Q000494:pharmacology*
D014665:Vasodilator Agents; D000241:Adenosine