COCAINE-INDUCED T-CELL PROLIFERATION IN THE RAT - ROLE OF AMYGDALA DOPAMINE D1 RECEPTORS

The immunomodulatory effects of local administration of cocaine into t he amygdala were studied in the rat. Intra-amygdala infusion of cocain e significantly and dose-dependently increased the proliferative respo nse of splenocytes to concanavalin A (Con A). A similar effect on the immune response was also observed in rats, microinfused into the centr al amygdala with the selective D1 receptor agonist SKF 38393. The incr ease of the proliferative response of splenocytes to Con A was inhibit ed by coinfusion within the central amygdala of the dopamine D1 recept or antagonist SCH 23390, together with cocaine, but not by coinfusion of the dopamine D2 receptor antagonist eticlopride. These results sugg est that cocaine may produce at least some of its effects on the immun e system through the activation of brain dopamine neurotransmission an d that the central amygdala may represent a critical structure mediati ng cocaine-induced T cell proliferation. (C) 1998 Elsevier Science Ire land Ltd. All rights reserved.