Estrogen effects on the hyperactivity induced by (+)-MDMA and cocaine in female rats.
This study compared the effects of estrogen (E) on the hyperactivity induced by (+)-3,4-methylenedioxymethamphetamine (MDMA) with E effects on cocaine-evoked hyperactivity in female rats. Sprague-Dawley rats were ovariectomized (OVX); half of them received a 17beta-estradiol (E2) implant (OVX + E). Three weeks later, rats received saline, (+)-MDMA (1, 2, or 4 mg/kg) or cocaine (5, 10, or 20 mg/kg), and locomotor activity was monitored. OVX + E rats exhibited greater locomotor hyperactivity in response to both psychostimulants than did OVX rats. The enhanced response to cocaine appeared within 5 min following drug injection whereas the enhanced response to (+)-MDMA was delayed for approximately 30 min. The differential effects of E on hyperactivity may be due to the unique profiles of DA and 5-HT in response to (+)-MDMA and cocaine.
Zhou
Wenxia
W
Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston 77555-1031, USA.
Cunningham
Kathryn A
KA
Thomas
Mary L
ML
D000818:Animals; D003042:Cocaine / Q000494:pharmacology*; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology*; D004958:Estradiol / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D006213:Hallucinogens / Q000494:pharmacology*; D009043:Motor Activity / Q000187:drug effects*; D018817:N-Methyl-3,4-methylenedioxyamphetamine / Q000494:pharmacology*; D010052:Ovariectomy / Q000662:veterinary; D051381:Rats; D017207:Rats, Sprague-Dawley
D018765:Dopamine Uptake Inhibitors; D006213:Hallucinogens; D004958:Estradiol; D003042:Cocaine; D018817:N-Methyl-3,4-methylenedioxyamphetamine