title: Beneficial effects of L-arginine on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced neuronal degeneration in substantia nigra of Balb/c mice.
abstract: BACKGROUND
  L-arginine has been recently investigated and proposed to reduce neurological damage after various experimental models of neuronal cellular damage. In this study, we aim to evaluate the beneficial effects of L-arginine administration on the numerical density of dark neurons (DNs) in the substantia nigra pars compacta (SNc) of Balb/c mice subjected to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) administration.
  
  
  METHODS
  Male Balb/c mice were randomly divided into 4 groups (n = 7 each): MPTP only; saline only (control); MPTP + L-arginine; and L-arginine only. The animals were infused intranasally with a single intranasal administration of the proneurotoxin MPTP (1 mg/nostril). L-arginine (300 mg/kg) was administrated intraperitoneally once daily for 1-week starting from 3 days after MPTP administration. Cavalieri principle method was used to estimate the numerical density of DNs in the SNc of different studied groups.
  
  
  RESULTS
  Twenty days following MPTP administration, the number of DNs was significantly increased when compared to sham-control and L-arginine-control groups (P < 0.05). Nevertheless, our results showed that L-arginine administration significantly decreased the numerical density of DNs in SNc of mice.
  
  
  CONCLUSIONS
  This investigation provides new insights in experimental models of Parkinson's disease, indicating that L-arginine represents a potential treatment agent for dopaminergic neuron degeneration in SNc observed in Parkinson's disease patients.
authors.affiliation: Department of Anatomical Sciences, School of Medicine, Birjand University of Medical Sciences, Birjand, Iran.
authors.forename: Javad
authors.initials: J
authors.lastname: Hami
authors.affiliation: Department of Public Health, Research Centre of Experimental Medicine, Deputy of Research and Technology, Birjand University of Medical Sciences, Birjand, Iran.
authors.forename: Mehran
authors.initials: M
authors.lastname: Hosseini
authors.affiliation: Department of Anatomical Sciences, School of Medicine, Birjand University of Medical Sciences, Birjand, Iran.
authors.forename: Saeed Vafaei
authors.initials: SV
authors.lastname: Nezhad
authors.affiliation: Department of Biology, School of Sciences, Payam-e-Noor University, Tehran, Iran.
authors.forename: Sekineh
authors.initials: S
authors.lastname: Shahi
authors.affiliation: Department of Anatomical Sciences, School of Medicine, Birjand University of Medical Sciences, Birjand, Iran.
authors.forename: Nassim
authors.initials: N
authors.lastname: Lotfi
authors.affiliation: Student of Medicine, Department of Anatomical Sciences, School of Medicine, Birjand University of Medical Sciences, Birjand, Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Ehsani
authors.affiliation: Department of Anatomical Sciences and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Akram
authors.initials: A
authors.lastname: Sadeghi
keywords: 1-methyl-4-phenyl-1; 2; 3; 6 tetrahydropyridine; Balb/c mice; L-arginine; substantia nigra