title: [Cerebral uptake and regional cerebral distribution of propofol under concentration equilibrium condition in the internal carotid artery and internal jugular vein in dogs].
abstract: OBJECTIVE
  To investigate the cerebral uptake and regional distribution of propofol when plasma propofol concentration reaches equilibrium in the internal carotid artery and internal jugular vein in dogs.
  
  
  METHODS
  Eight male hybrid dogs aged 12-18 months weighing 10-12 kg were anesthetized with propofol at a single bolus (7 mg/kg) in 15 s followed by propofol infusion at a constant rate of 70 mg.kg(-1).h(-1) via the great saphenous vein of the right posterior limb. Blood samples were taken from the internal carotid artery and internal jugular vein at 30 min (T30) after propofol infusion for measurement of plasma propofol concentrations by high-pressure liquid chromatography (HPLC). The thalamus, epithalamus, metathalamus, hypothalamus, subthalamus, frontal lobe, parietal lobe, temporal lobe, hippocampus, cingulate gyrus, cerebellum, midbrain, pons, medulla oblongata and cervical cord were then dissected to determine propofol concentrations in these tissues by HPLC.
  
  
  RESULTS
  The propofol concentrations in the internal carotid artery and internal jugular vein blood plasma were comparable at T30 (6.16-/+1.02 vs 6.17-/+1.00 microg/ml, P>0.05). The propofol concentration was 6.11-/+1.07 microg/g in the epithalamus, 6.14-/+0.98 microg/g in the metathalamus, 6.12-/+1.02 microg/g in the hypothalamus, 6.15-/+1.00 microg/g in the subthalamus, 6.20-/+1.03 microg/g in the frontal lobe, 6.18-/+1.02 microg/g in the parietal lobe, 6.13-/+1.00 microg/g in the temporal lobe, 6.07-/+0.99 microg/g in the hippocampus, 6.14-/+1.06 microg/g in the cingulate gyrus, 6.15-/+1.00 microg/g in the cerebellum, 6.13-/+1.05 microg/g in the midbrain, 6.18-/+1.01 microg/g in the pons, 6.15-/+0.93 microg/g in the medulla oblongata, and 6.13-/+1.00 microg/g in the cervical cord, showing no significant differences in the distributions (P>0.05). Propofol concentration in the thalamus (8.68-/+0.88 microg/g) was significantly higher than those in the other brain tissues (P<0.05).
  
  
  CONCLUSIONS
  At the constant intravenous propofol injection rate of 70 mg.kg(-1).h(-1), plasma propofol concentration reaches equilibrium 30 min after the injection in the internal carotid artery and internal jugular vein with even distribution in the cerebral tissues in dogs, but the thalamus contains high propofol concentration.
authors.affiliation: Department of Anesthesiology, Nanfang Hospital, and Hygiene Inspection Center, Southern Medical University, Guangzhou 510515, China. lcsnfyy@126.com
authors.forename: Chun-shui
authors.initials: CS
authors.lastname: Lin
authors.forename: Feng-yong
authors.initials: FY
authors.lastname: Xie
authors.forename: Miao-ning
authors.initials: MN
authors.lastname: Gu
authors.forename: Chang-tao
authors.initials: CT
authors.lastname: Liu
authors.forename: Zhi-feng
authors.initials: ZF
authors.lastname: Zhou
mesh_terms: D000042:Absorption; D018686:Anesthetics, Intravenous / Q000097:blood / Q000493:pharmacokinetics; D000818:Animals; D001921:Brain / Q000378:metabolism*; D002343:Carotid Artery, Internal / Q000378:metabolism*; D004285:Dogs; D007601:Jugular Veins / Q000378:metabolism*; D008297:Male; D015742:Propofol / Q000097:blood / Q000493:pharmacokinetics*; D013788:Thalamus / Q000378:metabolism*
chemical_list: D018686:Anesthetics, Intravenous; D015742:Propofol