Low ambient temperature reveals distinct mechanisms for MDMA-induced serotonergic toxicity and astroglial Hsp27 heat shock response in rat brain

► Elevated Hsp27 protein expression after MDMA is related to the hyperthermic response. ► Increased Hsp27 level can be separated from serotonergic neurotoxicity caused by MDMA. ► Tph IHC is an early and sensitive method to demonstrate MDMA-caused vulnerability. ► Intrinsic Hsp27 induction is uneffective to protect serotonergic fibers to MDMA.