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We have previously demonstrated that adenosine controls the release of catecholamines (CA) from carotid body (CB) acting on A_2B receptors. Here, we have tested the hypothesis that the control is exerted via an interaction between adenosine A_2B and dopamine D₂ receptors present in chemoreceptor cells. Experiments were performed in vitro in CB from 3 months rats. The effect of A_2B adenosine and D₂ dopamine agonists and antagonists applied alone or in combination were studied on basal (20%O₂) and hypoxia (10%O₂)‐evoked release of CA and cAMP content of CB. We have found that adenosine A₂ agonists and D₂ antagonists dose‐dependently increased basal and evoked release CA from the CB while A₂ antagonists and D₂ agonists had an inhibitory action. The existence of A_2B‐D₂ receptor interaction was established because the inhibitory action of A₂ antagonists was abolished by D₂ …