title: Alpha II Spectrin breakdown products in immature Sprague Dawley rat hippocampus and cortex after traumatic brain injury.
abstract: After traumatic brain injury (TBI), proteolysis of Alpha II Spectrin by Calpain 1 produces 145 Spectrin breakdown products (SBDPs) while proteolysis by Caspase 3 produces 120 SBDPs. 145 and 120 SBDP immunoblotting reflects the relative importance of caspase-dependent apoptosis or calpain-dependent excitotoxic/necrotoxic cell death in brain regions over time. In the adult rat, controlled cortical impact (CCI) increased 120 SBDPs in the first hours, lasting a few days, and increased 145 SBDPs within the first few days lasting up to 14 days after injury. Little is known about SBDPs in the immature brain after TBI. Since development affects susceptibility to apoptosis after TBI, we hypothesized that CCI would increase 145 and 120 SBDPs in the immature rat brain relative to SHAM during the first 3 and 5 days, respectively. SBDPs were measured in hippocampi and cortices at post injury days (PID) 1, 2, 3, 5, 7 and 14 after CCI or SHAM surgery in the 17 day old Sprague Dawley rat. 145 SBDPs increased in both brain tissues ipsilateral to injury during the first 3 days, while changes in contralateral tissues were limited to PID2 cortex. 145 SBDPs elevations were more marked and enduring in hippocampus than in cortex. Against expectations, 120 SBDPs only increased in PID1 hippocampus and PID2 cortex. 145 SBDPs elevations occurred early after CCI, similar to previous studies in the adult rat, but resolved more quickly. The minimal changes in 120 SBDPs suggest that calpain-dependent, but not caspase-dependent, cell death predominates in the 17 day old rat after CCI.
authors.affiliation: Department of Pediatrics, Division of Critical Care, University of Utah School of Medicine, Salt Lake City, UT 84132, United States. Electronic address: michelle.schober@hsc.utah.edu.
authors.forename: Michelle E
authors.initials: ME
authors.lastname: Schober
authors.affiliation: Department of Pediatrics, Division of Neonatology, University of Utah, Salt Lake City, UT 84132, United States.
authors.forename: Daniela F
authors.initials: DF
authors.lastname: Requena
authors.affiliation: Department of Pediatrics, Division of Neonatology, University of Utah, Salt Lake City, UT 84132, United States.
authors.forename: Lizeth J
authors.initials: LJ
authors.lastname: Davis
authors.affiliation: Department of Surgery, University of Utah, Salt Lake City, UT 84132, United States.
authors.forename: Ryan R
authors.initials: RR
authors.lastname: Metzger
authors.affiliation: Department of Pediatrics, Division of Critical Care, University of Utah School of Medicine, Salt Lake City, UT 84132, United States.
authors.forename: Kimberly S
authors.initials: KS
authors.lastname: Bennett
authors.affiliation: Department of Pediatrics, Division of Neurology, University of Utah, Salt Lake City, UT 84132, United States.
authors.forename: Denise
authors.initials: D
authors.lastname: Morita
authors.affiliation: Department of Pediatrics, Division of Physical Medicine and Rehabilitation, University of Utah, Salt Lake City, UT 84132, United States.
authors.forename: Christian
authors.initials: C
authors.lastname: Niedzwecki
authors.affiliation: Department of Pediatrics, Center for Neuroproteomics & Biomarker Research, Department of Psychiatry, University of Florida, Gainsville, FL 32611, United States.
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Department of Pediatrics, Center for Neuroproteomics & Biomarker Research, Department of Psychiatry, University of Florida, Gainsville, FL 32611, United States.
authors.forename: Kevin K W
authors.initials: KK
authors.lastname: Wang
mesh_terms: D000818:Animals; D001930:Brain Injuries / Q000503:physiopathology*; D016923:Cell Death / Q000502:physiology; D002540:Cerebral Cortex / Q000254:growth & development / Q000503:physiopathology*; D004195:Disease Models, Animal; D007839:Functional Laterality; D006624:Hippocampus / Q000254:growth & development / Q000503:physiopathology*; D015151:Immunoblotting; D008297:Male; D011897:Random Allocation; D017207:Rats, Sprague-Dawley; D013049:Spectrin / Q000378:metabolism*; D013997:Time Factors
chemical_list: D013049:Spectrin
keywords: Apoptosis; Cell death; Controlled cortical impact; Developmental; Excitotoxicity