Age-associated changes on axonal regeneration and functional outcome after spinal cord injury in rats.

  • Amrollah Roozbehi Department of Anatomy, Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran.
  • Mohammad Taghi Joghataei Department of Anatomy, Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran.
  • Mehrdad Bakhtiyari Department of Anatomy, Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran.
  • Jamshid Mohammadi Department of Physiology, Herbal Medicine Research Center, Yasuj University of Medical Sciences, Yasuj, Iran.
  • Parastou Rad Department of Midwifery, School of Midwifery, Yasuj University of Medical Sciences, Yasuj, Iran.
  • Hamdollah Delaviz Department of Anatomy, Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran.
Keywords: Age, Axonal regeneration, Functional recovery, Spinal cord hemisection


This study was conducted to evaluate the association between aging and regenerative potential of spinal cord injury. Three groups of male Sprague-Dawley rats, including young (40 days), mature (5-6 months) and old (28-29 months) were spinally hemisected at the L1 level. The locomotor performance was assessed weekly for eight weeks after lesion using locomotors' rating scale developed by Basso, Bresnahan and Beattie (BBB). In the tracing study, retrograde labeled neuron was counted in the lateral vestibular nucleus for axonal regeneration. From 4-8 weeks, the functional recovery of the young and mature age rats was significantly increased in comparison to the old age group. At 8 weeks, young and mature animals achieved a plateau score of (mean ± SD), 17 ± 1.47 and 16.8 ± 0.70 respectively, and the old rats reached an average score of 13.8±1.63 (P<0.05). The mean number of labeled neurons in the vestibular nucleus in the young group (mean ± SD): 32.05 ± 1.03 increase significantly compared to the older age group 5.01 ± 1.31 (P<0.05). Current findings suggest that axonal repair and functional improvement decrease in aged animals after partial spinal cord injury. Thus, the aging process may affect the regenerative capacity of the injured central nervous system, and axonal regeneration is age dependent.


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How to Cite
Roozbehi A, Joghataei MT, Bakhtiyari M, Mohammadi J, Rad P, Delaviz H. Age-associated changes on axonal regeneration and functional outcome after spinal cord injury in rats. Acta Med Iran. 53(5):281-286.