title: [Effect of electroacupuncture combined with intragastric administration of borneol on the permeability of blood-brain barrier in the mouse].
abstract: OBJECTIVE
  To observe the effect of electroacupuncture (EA) combined with gavage of borneol on the permeability and ultrastructure of the blood-brain barrier (BBB) in mice, so as to reveal its mechanism underlying improving permeability of BBB.
  
  
  METHODS
  For assaying Evans blue (EB) content in the brain, 60 Kunming mice were evenly divided into control, EA, borneol (0.2 g/kg, borneol-0.2), borneol (0.4 g/kg, borneol-0.4), borneol (0.2 g/kg, borneol-0.2) + EA and borneol (0.4 g/kg, borneol-0.4) + EA groups. For determination of P-glycoprotein [P-gp, a member of the superfamily of ATP-binding cassette (ABC) transporters which transport various molecules across extra- and intra-cellular membranes] function and the ultrastructure of BBB, other 84 mice were randomized into control, borneol-0.2, borneol-0.4, borneol-0.2 + EA, borneol-0.4 + EA and verapamil groups (n=10 for P-gp. function analysis, and n 2 for electron microscopic observation). EA (2 Hz, 1 mA) was applied to "Baihui" (GV 20) and "Yamen"(GV 15) for 20 ml once daily for 14 days. EB (2.5%, 0.2 mL/kg) and rhodamine (Rh) 123 (0.2 mg/kg) were injected intravenously first through the tail vein, and their contents in the brain and Rh 123 in the plasma were detected after EA by using an ultraviolet fluorescence microplate reader. At the same time, the permeation index (Kp) was calculated by the ratio of Rh 123brain/Rh 123blood.
  
  
  RESULTS
  Compared with the control group, the cerebral EB and Rh 123 contents and Kp of BBB in the EA, borneol-0.2, borneol-0.4, borneol-0.2 + EA, borneol-0.4 + EA and verapamil groups were increased significantly (P < 0.05, P < 0.01). The cerebral EB content was significantly higher in the borneol-0.2 + EA group than in the borneol-0.2 group (P < 0.05), suggesting a synergistic effect of EA and borneol. No significant differences were found among the EA, borneol-0.2 and borneol-0.4 groups in cerebral EB levels, among the control, EA, borneol-0.2, borneol-0.4, borneol-0.2 + EA, borneol-0.4 + EA and verapamil groups in plasma Rh 123 contents, and among the EA, borneol-0.2, borneol-0.4, borneol-0.2 + EA, borneol-0.4 + EA and verapamil groups in cerebral Rh 123 contents and Kp of BBB (P > 0.05). Results of the electron transmission microscope showed that the compact degree of the tight junction of BBB was decreased in the borneol-0.2, borneol-0.4, borneol-0.2 + EA, borneol-0.4 + EA groups but not in the EA group.
  
  
  CONCLUSIONS
  EA and gavage of borneol treatments may enhance the permeability of BBB for EB and Rh 123 and have a certain synergistic effect in mice. The effect of borneol may be closely with the inhibition of P-glycoprotein and the decrease of tight junction of BBB while the effect of EA treatment is probably related to the inhibition of P-glycoprotein only.
authors.affiliation: Key Laboratory of Integrated Acupuncture and Drugs Constructed by Jiangsu Province and Chinese Ministry of Education, Nanjing University of Chinese Medicine, Nanjing 210046, China. yubinruming@sina.com
authors.forename: Bin
authors.initials: B
authors.lastname: Yu
authors.forename: Gao-hong
authors.initials: GH
authors.lastname: Lü
authors.forename: Yong
authors.initials: Y
authors.lastname: Sun
authors.forename: Xin
authors.initials: X
authors.lastname: Lin
authors.forename: Tai-hui
authors.initials: TH
authors.lastname: Fang
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism; D000818:Animals; D001812:Blood-Brain Barrier / Q000187:drug effects / Q000378:metabolism*; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D001892:Camphanes / Q000008:administration & dosage*; D002463:Cell Membrane Permeability; D003131:Combined Modality Therapy; D015671:Electroacupuncture; D005260:Female; D008297:Male; D051379:Mice; D023421:Models, Animal
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D001892:Camphanes; C022871:isoborneol