title: Long-term behavioral deficits and recovery after transient ischemia in middle-aged rats: Effects of behavioral testing.
abstract: OBJECTIVE
  Most pre-clinical stroke studies address the acute phase after injury, with less attention to long-term effects of injury, treatment, and experimental testing itself. We addressed these questions: 1) Will functional deficits persist up to 8 weeks following transient stroke in older animals? 2) Will functional deficits resolve spontaneously, with time and/or repeated behavioral testing?
  
  
  METHODS
  Male Sprague-Dawley rats (12 months) were pre-trained on behavioral tasks to provide baseline data and then underwent transient middle artery occlusion (tMCAO) or sham surgery. We measured motor, sensory, cognitive and gait impairments over 8 weeks, and the extent of hemispheric brain infarction. One cohort underwent behavioral testing once at 8 weeks post-stroke (LT); a second cohort (RLT) was tested at 3, 6 and 8 weeks post-stroke.
  
  
  RESULTS
  Significant deficits were exhibited in all functional outcomes in both cohorts after 8 weeks. We observed some recovery in some behavioral parameters in both cohorts at 8 weeks.
  
  
  CONCLUSIONS
  Deficits persist for at least 8 weeks after tMCAO. The greater spontaneous recovery seen in the RLT groups suggest that repeated testing did reduce the severity of these stroke-induced impairments. These findings have implications for designing future studies of agents to induce long-term functional recovery following stroke.
authors.forename: Seema
authors.initials: S
authors.lastname: Yousuf
authors.forename: Fahim
authors.initials: F
authors.lastname: Atif
authors.forename: Iqbal
authors.initials: I
authors.lastname: Sayeed
authors.forename: Huiling
authors.initials: H
authors.lastname: Tang
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
authors.forename: Donald G
authors.initials: DG
authors.lastname: Stein
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D001921:Brain / Q000503:physiopathology*; D003071:Cognition / Q000502:physiology*; D005684:Gait / Q000502:physiology; D002546:Ischemic Attack, Transient / Q000503:physiopathology*; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020127:Recovery of Function / Q000502:physiology*; D020521:Stroke / Q000503:physiopathology*
keywords: Aged rats; behavior; long-term functional deficits; stroke; sub-acute phase