title: Diabetes mellitus type 1 induces dark neuron formation in the dentate gyrus: a study by Gallyas' method and transmission electron microscopy.
abstract: BACKGROUND
  Diabetes mellitus type 1 is a chronic endogenous stressor. We investigated the effects of a diabetes mellitus type 1 on dark neuron formation in granular layer of dentate gyrus.
  
  
  METHODS
  Diabetes was induced by a single intraperitoneal (IP) injection of streptozotocin (STZ) at a dose of 60 mg/kg dissolved in saline. Control animals were received only saline. In the end of eight weeks, the brains were removed and hippocampi studied by Gallyas' method and transmission electron microscopy.
  
  
  RESULTS
  The comparison between the rate of dark neurons in diabetic group (223 ± 25) and of control (5.75 ± 4.34) showed significant level of difference (p<0.05). Ultrastructurally dark neurons showed apoptotic death criteria namely: dark and electron dense appearance, chromatin condensation, margination and clumping.
  
  
  CONCLUSIONS
  Present results suggest that STZ-induced diabetes accelerates dark neuron formation with apoptotic criteria in granule layer of dentate gyrus.
authors.affiliation: Department of Anatomy, Medicine School, North Khorasan University of Medical Sciences (NKUMS), Bojnourd, Iran. shahahmadpour@gmail.com
authors.forename: S H
authors.initials: SH
authors.lastname: Ahmadpour
authors.forename: H
authors.initials: H
authors.lastname: Haghir
mesh_terms: D000818:Animals; D018891:Dentate Gyrus / Q000473:pathology* / Q000648:ultrastructure*; D003922:Diabetes Mellitus, Type 1 / Q000473:pathology*; D008297:Male; D046529:Microscopy, Electron, Transmission; D009474:Neurons / Q000473:pathology* / Q000648:ultrastructure*; D051381:Rats; D017208:Rats, Wistar; D013194:Staining and Labeling / Q000379:methods*