Wheel running increases hyperthermia and mortality rate following 3,4-methylenedioxymethamphetamine (MDMA) in rats
preprint DOI: 10.1101/126706
Summary
Sustained physical activity significantly increases hyperthermic responses to MDMA in male Wistar rats, particularly at higher ambient temperatures. The study found that administering 10 mg/kg of MDMA resulted in increased body temperature and activity levels, with greater mortality observed when the rats had access to an activity wheel compared to when they did not. This suggests that physical activity could be a risk factor for adverse reactions to MDMA in humans.
Study at a glance
| Design | experimental study |
|---|---|
| Population | male Wistar rats |
| Key finding | Increased physical activity exacerbates hyperthermia and mortality associated with MDMA use. |
Abstract
Abstract Hyperthermic responses are commonly reported in cases of human medical emergency following recreational use of 3,4-methylenedioxymethamphetamine (MDMA, “Ecstasy”), but a precise determination of contributing environmental factors has been elusive given the relative scarcity of threatening and fatal reactions in humans. This study was conducted to determine if elevated physical activity contributes to hyperthermic responses to MDMA in a well controlled animal model. Unrestrained male Wistar rats were monitored with minimally-invasive radiotelemetry techniques following challenge with MDMA (1.0, 5.6 and 10.0 mg/kg, s.c.). Studies were conducted in low (23-25°C) and high (27°C) ambient temperature (T A ), with and without access to an activity wheel. The study confirmed dose dependent effects on body temperature, chamber activity and wheel activity which were modified by different T A conditions. Increases in wheel and home chamber activity produced by 10 mg/kg MDMA increased the magnitude of hyperthermia under 27°C T A . Furthermore, greater subject mortality was observed in the wheel-access condition compared with the no-wheel condition. These data provide direct evidence that sustained physical activity increases the hyperthermic response to MDMA and that this is associated with increased lethality. This is the first direct experimental confirmation that increased physical activity may be a risk factor for adverse reactions to MDMA in human user populations.