J Vet Sci.  2011 Jun;12(2):143-149. 10.4142/jvs.2011.12.2.143.

Comparison of bare metal stent and paclitaxel-eluting stent using a novel rat aorta stent model

• Kwon JS
• Park RK
• Shim TJ
• Jeong MH
• Cho MC
• Ahn Y
• Kim DW

• KMID: 1106556
• DOI: http://doi.org/10.4142/jvs.2011.12.2.143

Abstract

The purpose of our study was to create a novel rat aorta stent implantation model. Stainless steel bare metal stents (BMS) or paclitaxel-eluting stents (PES) were implanted in male Sprague-Dawley rats (BW 400 +/- 20 g). Two and four weeks after stent implantation, the aorta were collected, fixed with 2% glutaraldehyde, and cut into two segments. One segment was used for scanning electron microscopy analysis to evaluate re-endothelialization, and the other segment was used to calculate the neointimal area. At 2 weeks after stenting, the appearance of neointimal hyperplasia was less in the PES group than in the BMS group. At 4 weeks after stenting, no significant difference in neointimal hyperplasia was observed between two groups. On the other hand, the PES group showed more thrombus formation and less re-endothelialization compared to the BMS group. This study demonstrated the ability of a novel rat model of aorta stenting via a common carotid artery to measure the efficacy and safety of commercially available drug-eluting stents.

Keyword

aorta; neointimal hyperplasia; rat; re-endothelialization; stents

MeSH Terms

Angioplasty/*methods
Animals
Aorta, Thoracic/*surgery/ultrastructure
Coronary Artery Disease/*surgery
*Drug-Eluting Stents
Histocytochemistry
Male
Microscopy, Electron, Scanning
Models, Animal
Neointima/pathology
Paclitaxel/*administration & dosage
Rats
Rats, Sprague-Dawley

Figure

• 

  Fig. 1 Establishment of a novel aorta stent implantation procedure in rats. Representative illustrations and fluoroscopic angiographs of the implantation of a bare metal stent or paclitaxel-eluting stent in the thoracic aorta. (A) Operation procedure. (B) and (C) Operation procedure involved a guide wire that was advanced in the thoracic aorta after excision of the left common carotid artery and a stent inserted into the thoracic aorta. (D) Follow-up thoracic angiography was performed with a catheter in the right common carotid artery.

• 

  Fig. 2 (A) 2 weeks (wk) and (B) 4 wk after implantation of the bare metal stent (BMS) or paclitaxel-eluting stent (PES). (C) Thrombus in the outer and inner area of the neointima at 4 wk. Scale bars = Aa and b, Ba and b: 1 mm; Ac and d, Bc and d, C: 50 µm. H&E stain.

• 

  Fig. 3 Histomorphometric results of BMS or PES implantation. (A) Neointimal area. (B) Representation of neointimal area, media area (green line) and inner luminal area (square line). (C) Uncovered strut ratio. (D) Focal thrombus ratio. BMS 2 wk vs. PES 2 wk (*p < 0.05). BMS 4 wk vs. PES 4 wk (**p < 0.05), BMS 2 wk vs. BMS 4 wk (#p < 0.05), PES 2 wk vs. PES 4 wk (##p < 0.05).

• 

  Fig. 4 Scanning electron microscopy photographs of BMS and PES in rat aorta. (A) Representation of strut area (blue) and uncovered area (red). (B) BMS and PES at 2 wk and (C) at 4 wk. (D) The covered stent ratio at 4 wk after stent implantation. (E) High magnification. Endothelial cells (green arrow), inflammatory cells (yellow arrow), and stent strut (red arrow). *p < 0.05. Ba and Ea: BMS 2 wk, Bb and Eb: PES 2 wk, Ca and Ec: BMS 4 wk, Cb and Ed: PES 4 wk. Scale bars = Aa: 500 µm, B and C: 1 mm, Ea and b: 100 µm, Ec and d: 50 µm.

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