MOTOR SYSTEMOvarian steroids and raloxifene prevent MPTP-induced dopamine depletion in miceGrandbois, Michelle1,2; Morissette, Marc1,2; Callier, Sophie1,2,3; Di Paolo, Thérèse1,2,4Author Information 1Oncology and Molecular Endocrinology Research Center, Laval University Medical Center (CHUL), 2705, Laurier boulevard, Sainte-Foy, Québec, PQ, G1V 4G2 2Faculty of Pharmacy, Laval University, Québec, PQ, G1K 7P4 Canada 3INSERM Unit 339, St-Antoine Hospital, 75012 Paris, France 4Corresponding author and address: Thérèse Di, Oncology and Molecular Endocrinology Research Center, Laval University Medical Center (CHUL), 2705, Laurier boulevard, Sainte-Foy, Québec, PQ, G1V 4G2 Received 17 August 1999; accepted 26 November 1999 Acknowledgements: Supported by MRC, Canada. Thanks to F. Labrie for raloxifene. NeuroReport: February 7, 2000 - Volume 11 - Issue 2 - p 343-346 Buy Abstract The activity of steroids was studied in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) lesioned retired breeder C57BL/6 male mice as a model of Parkinson's disease. Steroids were injected daily for 5 days before MPTP (4 injections, 15 mg/kg i.p., at 2 h intervals) and hormonal treatment continued for 5 more days. Mice that received 17β-estradiol or progesterone or raloxifene (a selective estrogen receptor modulator) and MPTP had striatal concentrations of dopamine (DA) and its metabolites dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) similar to those in control animals, whereas mice that received MPTP alone or with 17β-estradiol (the isomer with weak estrogenic activity) had an extensive decrease of DA and its metabolites. These results suggest stereospecific prevention of MPTP-induced dopamine loss by 17β-estradiol, which is also observed with progesterone and raloxifene. © 2000 Lippincott Williams & Wilkins, Inc.