Effects of L-type calcium channel antagonists on the serotonin-depleting actions of MDMA in rats.
The calcium channel antagonists verapamil nifedipine and flunarizine all increased the threshold for convulsions induced by N-methyl-D-aspartate in rats. By contrast, only flunarizine blocked the long-term serotonin-depleting effects of 3,4-methylenedioxymethamphetamine. Flunarizine was also the only drug that antagonized methamphetamine-induced stereotypy. These findings suggest that calcium influx through L-type channels does not participate in the neurotoxic mechanism of MDMA, and that the neuroprotective actions of flunarizine are probably related to its anti-dopaminergic activity.
Finnegan
K T
KT
Psychiatry Service, Veterans Administration Medical Center, Salt Lake City, UT 84148.
Calder
L
L
Clikeman
J
J
Wei
S
S
Karler
R
R
D015104:3,4-Methylenedioxyamphetamine / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors / Q000494:pharmacology; D000818:Animals; D001923:Brain Chemistry / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism; D005444:Flunarizine / Q000494:pharmacology; D006220:Haloperidol / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008694:Methamphetamine / Q000037:antagonists & inhibitors / Q000494:pharmacology; D018817:N-Methyl-3,4-methylenedioxyamphetamine; D009543:Nifedipine / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012640:Seizures / Q000139:chemically induced / Q000517:prevention & control; D012701:Serotonin / Q000378:metabolism*; D013239:Stereotyped Behavior / Q000187:drug effects; D014700:Verapamil / Q000494:pharmacology
D002121:Calcium Channel Blockers; D012701:Serotonin; D008694:Methamphetamine; D015104:3,4-Methylenedioxyamphetamine; D014700:Verapamil; D009543:Nifedipine; D006220:Haloperidol; D018817:N-Methyl-3,4-methylenedioxyamphetamine; D005444:Flunarizine