Effects of repeated systemic administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) on striatal tyrosine hydroxylase activity in vitro and tyrosine hydroxylase content.
We examined both in vitro tyrosine hydroxylase (TH) activity and TH content determined by a new enzyme immunoassay in the mouse striatum after repeated systemic injection of MPTP. Repeated systemic administration of MPTP to mice (30 mg/kg per day, subcutaneously for 8 days) caused an approximately 65% decrease of both TH activity and TH content in the striatum. The intensity of immunohistochemical staining of TH protein in the striatum was also reduced in MPTP-treated mice. These results indicate that the reduction of TH activity in vitro after the repeated administration of MPTP is due to reduction of TH protein as a result of nerve degeneration.
D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D000818:Animals; D003342:Corpus Striatum / Q000187:drug effects / Q000201:enzymology*; D004298:Dopamine / Q000378:metabolism; D007150:Immunohistochemistry; D007158:Immunologic Techniques; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D011725:Pyridines / Q000008:administration & dosage* / Q000494:pharmacology; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism*
D011725:Pyridines; D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine