Figure 1.

Effect of haloperidol (Hal) on MDMA-induced hyperthermia. (a) Rectal temperature of rats injected with saline or MDMA (15 mg kg⁻¹ i.p.) at time zero and rats injected with haloperidol (2 mg kg⁻¹ i.p.) at −5 min and +55 min and treated with MDMA at time zero. There was no difference in the basal temperature of the groups. MDMA produced a significant rise in body temperature (F(1,10)=19.89, P<0.01) compared with the saline injected group. Administration of haloperidol to MDMA-treated rats prevented the MDMA-induced hyperthermia (F(1,11)=27.16, P<0.001). (b) Effect of haloperidol on MDMA-induced hyperthermia when rats injected with haloperidol+MDMA were kept at high ambient temperature. Temperature of rats given haloperidol and saline is also shown. There was no difference in basal temperature of the groups. Using the homeothermic blanket, the rectal temperature of the haloperidol+MDMA-treated rats was significantly higher than that of the saline group (F(1,10)=141.69, P<0.001). All results shown as means±s.e.mean of n=4–6 rats.