Effects of activation and blockade of dopamine D(2) receptors on the immune response in mice with different types of behavior.

Activation of dopamine D(2) receptors by the selective agonist quinpirole was found to lead to immunostimulation in control (no experience of confrontations) C57BL/6J mice and in mice subjected to psychoemotional tension (aggression and submission). The most marked increase in the immune response was seen on formation of the aggressive and submissive behavioral strategies. The effects of blockade of D(2) dopamine receptors by haloperidol-immunosuppression-were seen only in control and aggressive animals, but were not seen in animals with submissive behavior. The question of the significance of the initial psychoemotional state, which is linked with particular neurotransmitter patterns in the brain (levels of dopamine, serotonin, their metabolites; dopamine receptor activity in subcortical structures), for the effects of agents altering the activity of dopamine D(2) receptors on the immune response is discussed.