Mild experimental brain injury in the rat induces cognitive deficits associated with regional neuronal loss in the hippocampus

J Neurotrauma. 1993 Winter;10(4):405-14. doi: 10.1089/neu.1993.10.405.


Memory dysfunction following mild human traumatic brain injury (TBI) is a common clinical observation, but the pathologic substrate underlying this loss of function has not been well-characterized. In the present study, we examined the effects of a mild lateral fluid percussion (FP) brain injury on memory dysfunction, neuronal cell loss in specific regions of the hippocampus, and breakdown of the blood-brain barrier (BBB). A Morris Water Maze (MWM) memory paradigm was used to assess memory retention in rats 42 h after lateral FP brain injury (n = 11) or sham injury (n = 10). At the completion of cognitive testing, animals were sacrificed and neuronal cell loss in the hippocampi was examined with Nissl staining. Immunoreactivity to anti-rat IgG was used to evaluate the extent of BBB disruption. A significant correlation was observed between posttraumatic memory scores and neuronal loss in the hilus of the dentate gyrus (p < 0.005). To our knowledge, these observations are the first to suggest an association between cognitive deficits following a mild experimental brain injury and neuropathological changes in the hippocampus.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Blood Gas Analysis
  • Blood-Brain Barrier / physiology
  • Brain Concussion / complications
  • Brain Concussion / pathology*
  • Brain Concussion / psychology*
  • Cerebral Cortex / pathology
  • Cognition Disorders / etiology
  • Cognition Disorders / psychology*
  • Electroencephalography
  • Evoked Potentials / physiology
  • Hippocampus / pathology*
  • Immunohistochemistry
  • Male
  • Memory / physiology
  • Nerve Degeneration / physiology
  • Neurons / physiology*
  • Pyramidal Cells / physiology
  • Rats
  • Rats, Sprague-Dawley
  • Regression Analysis