ADENOSINE A(3) RECEPTOR STIMULATION AND CEREBRAL-ISCHEMIA

Chronic treatment with the selective adenosine A(3) receptor agonist N -6-(3-iodobenzyl)adenosine-5'-N-methylcarboxamide (IB-MECA) administer ed prior to either 10 or 20 min forebrain ischemia in gerbils resulted in improved postischemic cerebral blood circulation, survival, and ne uronal preservation. Opposite effects, i.e., impaired postischemic blo od flow, enhanced mortality, and extensive neuronal destruction in the hippocampus were seen when IB-MECA was given acutely. Neither adenosi ne A(1) nor A(2) receptors are involved in these actions. The data ind icate that stimulation of adenosine A(3) receptors may play an importa nt role in the development of ischemic damage, and that adenosine A(3) receptors may offer a new target for therapeutic interventions.