Dopamine 2 antagonists suppress the jumping escape behavior of mice exposed to heat

Abstract

It is generally accepted that the dopamine system in the nucleus accumbens is activated and is involved in avoidance and escape behavior under aversive conditions. This study shows that the central dopamine system is involved in the jumping escape behavior in mice exposed to heat. In this study, the dopamine catabolite ratio in the nucleus accumbens was increased and dopamine 2 (D2) antagonists, chlorpromazine and haloperidol, inhibited the jumping escape behavior in mice exposed to 38.5 °C. Chlorpromazine increased hyperthermia in mice exposed to 38.5 °C, while haloperidol had no effect on rectal temperature in mice exposed to 38.5 °C. These results indicate that D2 antagonists inhibit the jumping escape behavior in mice exposed to heat and the inhibition mechanism of D2 antagonists is independent of the disturbance of autonomic thermoregulation.