title: Laser Doppler flow and brain tissue PO2 after cortical impact injury complicated by secondary ischemia in rats treated with arginine.
abstract: BACKGROUND
  Traumatic brain injury (TBI) makes the brain susceptible to secondary insults such as ischemia. This study tested the hypothesis that L-arginine would increase regional CBF (rCBF) and brain tissue PO2 (PbtO2) at the injury site.
  
  
  METHODS
  A secondary insult model was employed in rodents. rCBF was measured with laser doppler flowmetry (LDF) and PbtO2 with a PO2 catheter at the impact site. Animals were randomized to receive L-arginine, D-arginine or saline intravenously, 5 minutes after impact.
  
  
  RESULTS
  In animals who received L-arginine, the percentage rCBF from baseline (%CBF) was higher at the impact site after impact (p < 0.001), during bilateral carotid occulation (BCO) (p = 0.001) and during reperfusion (p = 0.032). In contrast, PbtO2 was not significantly increased throughout the experiment for the L-arginine group.
  
  
  CONCLUSIONS
  Administration of L-arginine increased rCBF in the injured brain tissue, and resulted in better preservation of CBF during BCO than D-arginine and saline.
authors.affiliation: Department of Pediatrics/Emergency Medicine, Baylor College of Medicine, Houston, Texas 77030, USA. drmendez@texaschildrenshospital.org
authors.forename: Donna R
authors.initials: DR
authors.lastname: Mendez
authors.forename: Leela
authors.initials: L
authors.lastname: Cherian
authors.forename: Claudia S
authors.initials: CS
authors.lastname: Robertson
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001120:Arginine / Q000494:pharmacology / Q000627:therapeutic use*; D001783:Blood Flow Velocity / Q000187:drug effects; D001784:Blood Gas Analysis; D001923:Brain Chemistry / Q000187:drug effects*; D001930:Brain Injuries / Q000150:complications*; D002545:Brain Ischemia / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology / Q000517:prevention & control*; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical; D006439:Hemodynamics / Q000187:drug effects; D007262:Infusions, Intravenous; D007427:Intracranial Pressure / Q000187:drug effects; D017078:Laser-Doppler Flowmetry; D008297:Male; D009569:Nitric Oxide / Q000502:physiology; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption / Q000187:drug effects; D011897:Random Allocation; D051381:Rats; D020318:Rats, Long-Evans; D012965:Sodium Chloride / Q000627:therapeutic use; D013997:Time Factors
chemical_list: D009569:Nitric Oxide; D012965:Sodium Chloride; D001120:Arginine; D010100:Oxygen