Investigations on the effects of ''Ecstasy'' on cerebral glucose metabolism: an 18-FDG PET study

Purpose: The aim of the present study was to determine the acute effects of the 'Ecstasy' analogue MDE (3,4-methylendioxyethamphetamine) on the cerebral glucose metabolism (rMRGlu) of healthy volunteers. Method: In a randomised double-blind trial, 16 healthy volunteers without a history of drug abuse were examined with 18-FDG PET 110-120 minutes after oral administration of 2 mg/kg MDE (n=8) or placebo (n=8). Beginning two minutes prior to radiotracer injection, a constant cognitive stimulation was maintained for 32 minutes using a word repetition paradigm in order to ensure constant and comparable mental conditions during cerebral 18-FDG uptake. Individual brain anatomy was represented using T1-weighted 3D flash MRI, followed by manual regionalisation into 108 regions-of-interest and PET/MRI overlay. Absolute quantification of rMRGlu and comparison of glucose metabolism under MDE versus placebo were performed using Mann-Whitney U-test. Results: Absolute global MRGlu was not significantly changed under MDE versus placebo (MDE: 41,8±11,1 μmol/min/100 g, placebo: 50,1±18,1 μmol/min/100 g, p=0,298). The normalised regional metabolic data showed a significantly decreased rMRGlu in the bilateral frontal cortex: Left frontal posterior (-7.1%, p<0.05) and right prefrontal superior (-4.6%, p<0.05). On the other hand, rMRGlu was significantly increased in the bilateral cerebellum (right: +10.1%, p<0.05; left: +7.6%, p<0.05) and in the right putamen (+6.2%, p<0.05). Conclusions: The present study revealed acute neurometabolic changes under the 'Ecstasy' analogon MDE indicating a fronto-striato-cerebellar dysbalance with parallels to other psychotropic substances and various endogenous psychoses respectively. (orig.)