title: Tenascin-C-coated platinum coils for acceleration of organization of cavities and reduction of lumen size in a rat aneurysm model.
abstract: OBJECTIVE
  Detachable platinum coils are widely used in the endovascular treatment of intracranial aneurysms. The use of coil placement produces a higher incidence of aneurysm recurrence compared with surgical clipping. To reduce the incidence of recurrence by promoting clot organization, the authors designed a platinum coil coated with tenascin-C (TNC), an extracellular matrix glycoprotein, and then histologically examined tissue responses.
  
  
  METHODS
  Platinum coils were prepared by successive coatings with cationic polyethyleneimine and anionic heparin and then TNC or basic fibroblast growth factor (bFGF) was immobilized by affinity binding to the heparin. Six unmodified, six heparin-coated, six bFGF-coated, or eight TNC-coated platinum coils were inserted into ligated common carotid arteries (CCAs) of adult male rats, and CCA segments were harvested after 14 or 28 days. The percentages of organized areas occupying the luminal cavity in unmodified, heparin-coated, bFGF-coated, and TNC-coated groups were 4.8 +/- 4.6, 1.6 +/- 1.1, 17.9 +/- 10.7, and 93.4 +/- 6.9%, respectively. In addition, the mean lumen size in the TNC-coated group (0.35 +/- 0.23 mm2) was reduced to less than half that of the unmodified group (0.72 +/- 0.21 mm2). Immunohistochemical analysis revealed that alpha-smooth muscle actin-positive cells were a major cellular component of the organized tissue within the TNC-coated coils but not in the bFGF group. Collagen fibrils in the organized areas were also much thicker and denser with TNC-coated coils than with bFGF-coated coils.
  
  
  CONCLUSIONS
  Placement of TNC-coated coils can remarkably accelerate organization of luminal cavities and reduce their volume, providing improved efficacy of these coils for endovascular embolization.
authors.affiliation: Department of Neurosurgery, Mie University School of Medicine, Tsu, Japan. ntoma@clin.medic.mie-u.ac.jp
authors.forename: Naoki
authors.initials: N
authors.lastname: Toma
authors.forename: Kyoko
authors.initials: K
authors.lastname: Imanaka-Yoshida
authors.forename: Taku
authors.initials: T
authors.lastname: Takeuchi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Matsushima
authors.forename: Hiroo
authors.initials: H
authors.lastname: Iwata
authors.forename: Toshimichi
authors.initials: T
authors.lastname: Yoshida
authors.forename: Waro
authors.initials: W
authors.lastname: Taki
mesh_terms: D000818:Animals; D002340:Carotid Artery Diseases / Q000628:therapy / Q000662:veterinary; D004617:Embolism / Q000517:prevention & control; D004621:Embolization, Therapeutic / Q000295:instrumentation* / Q000379:methods* / Q000662:veterinary; D004867:Equipment Design; D002532:Intracranial Aneurysm / Q000628:therapy* / Q000662:veterinary; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012008:Recurrence; D013525:Surgical Instruments; D019063:Tenascin / Q000008:administration & dosage* / Q000494:pharmacology
chemical_list: D019063:Tenascin