The effects on sexual behaviour of acute low doses of
methylendioxymethamphetamine (MDMA) (0.3, 1, 3 mg/kg/i.p.), alone or in
combination with exposure to loud music (1 h stimulation), were investigated in
Wistar rats. Results indicate that acute MDMA, at dose of 3 mg/kg, notably
impaired copulatory behavior of sexually experienced male rats. In particular,
MDMA-exposed animals exhibited a significant increase in intromission and
ejaculation latencies as well as a significant decrease in percentage of rats
displaying copulatory activity (one intromission at least). Surprisingly, one
hour exposure to loud music, which per se resulted ineffective, antagonized the
suppressive effect of MDMA by increasing the percent of animals displaying sexual
activity. However, combined treatment of MDMA and music stimulation did not fully
restore normal sexual behavior as the animals reaching ejaculation still showed a
marked reduction of copulatory efficiency. These findings demonstrate that the
systemic administration of a single low dose of MDMA, alone or in combination
with loud music, which is commonly present in certain environments such as rave
parties, notably impairs copulatory activity of male rats