Table 2.

5-Hydroxytryptamine synthesis rate constant (h⁻¹) in brain regions at various times following administration of MDMA (12.5 mg kg⁻¹) at a room temperature of 22°C

Time (weeks)	Cortex		Hippocampus		Striatum
	Saline	MDMA	Saline	MDMA	Saline	MDMA
1	0.83	0.97	0.77	0.72	0.54	0.50
2	0.86	0.81	0.69	0.95	0.55	0.69
4	0.94	1.04	0.80	0.93	0.67	0.67
8	0.76	0.71	0.75	0.69	0.54	0.57
32	0.82	1.10	0.75	0.90	0.64	0.61
Mean±s.e.m	0.84±0.03	0.92±0.07	0.75±0.02	0.83±0.05	0.59±0.03	0.61±0.03

The amine synthesis rate constant (the reciprocal of the time required to replace amine pool) was determined by dividing the synthesis rate measured in Table 1 by the tissue concentration of 5-HT and is reported as time (h⁻¹); see Methods for full details.