[The central nervous system and inflammation: the role of opioid peptides].

Inhibition of human granulocyte aggregation was observed in the presence of morphine in a naloxone stereoselective way, while the opioid peptides were ineffective. In comparative studies Ca(+)+ (A23187) and dynorphin 1-9, per se, induced stimulation of arachidonic acid metabolites from granulocytes. In this regard dynorphin 1-9 may function as a mediator between the central nervous system and the inflammation.