title: Neurovascular coupling of the posterior cerebral artery in spinal cord injury: a pilot study.
abstract: OBJECTIVE
  To compare neurovascular coupling in the posterior cerebral artery (PCA) between those with spinal cord injury (SCI) and able bodied (AB) individuals.
  
  
  METHODS
  A total of seven SCI and seven AB were matched for age and sex. Measures included PCA velocity (PCAv), beat-by-beat blood pressure and end-tidal carbon dioxide. Posterior cerebral cortex activation was achieved by 10 cycles of (1) 30 s eyes closed (pre-stimulation), (2) 30 s reading (stimulation).
  
  
  RESULTS
  Blood pressure was significantly reduced in those with SCI (SBP: 100 ± 13 mmHg; DBP: 58 ± 13 mmHg) vs.
  121 ± 12 mmHg; DBP: 74 ± 9 mmHg) during both pre-stimulation and stimulation, but the relative increase was similar during the stimulation period. Changes in PCAv during stimulation were mitigated in the SCI group (6% ± 6%) vs. AB (29% ± 12%, P < 0.001). Heart rate and end-tidal carbon dioxide responded similarly between groups.
  
  
  CONCLUSIONS
  Clearly, NVC is impaired in those with SCI. This study may provide a link between poor perfusion of the posterior cerebral region (containing the medullary autonomic centres) and autonomic dysfunction after SCI.
authors: Cardiovascular Physiology and Rehabilitation Laboratory, Physical Activity Promotion and Chronic Disease Prevention Unit, University of British Columbia, Vancouver V6T 1Z1, Canada. andrei.krassioukov@vch.ca.
authors: Aaron A
authors: AA
authors: Phillips
authors: International Collaboration of Repair Discoveries, University of British Columbia, Vancouver V6T 1Z1, Canada. andrei.krassioukov@vch.ca.
authors: Andrei V
authors: AV
authors: Krassioukov
authors: Cardiovascular Physiology and Rehabilitation Laboratory, Physical Activity Promotion and Chronic Disease Prevention Unit, University of British Columbia, Vancouver V6T 1Z1, Canada. meimuzizheng@hotmail.com.
authors: Mei Mu Zi
authors: MM
authors: Zheng
authors: Cardiovascular Physiology and Rehabilitation Laboratory, Physical Activity Promotion and Chronic Disease Prevention Unit, University of British Columbia, Vancouver V6T 1Z1, Canada. andrei.krassioukov@vch.ca.
authors: Darren E R
authors: DE
authors: Warburton