Article Text

PDF
Gamma-Irradiation Markedly Inhibits the Hydrated Collagen Gel Contraction by Arterial Smooth Muscle Cells
  1. Pierre-Frederic Keller,
  2. Vitali Verin,
  3. Thierry Ziegler,
  4. Bernadette Mermillod,
  5. Youri Popowski,
  6. Patrice Delafontaine
  1. 1From the Departments of Cardiology (P.-F.K., V.V., P.D.), University Hospital, Geneva, Switzerland,
  2. 2Medical Informatics (B.M.), University Hospital, Geneva, Switzerland,
  3. 3Radiation Oncology (Y.P.), University Hospital, Geneva, Switzerland,
  4. 4Department of Hypertension (T.Z.), CHUV, Lausanne, Switzerland.
  1. This work was supported by National Institutes of Health grants HL-45317, HL-47035, and DK-45215 and by the Swiss National Science Foundation (FNSR3100-050799.97), the Swiss Cardiology Foundation, and the Gerbex-Bourget Foundation.
  2. This study was presented as an oral presentation in the session of the new approaches to restenosis prevention at the 49th Annual Scientific Session of the American College of Cardiology in Anaheim, Calif., March 13, 2000.
  3. Address correspondence to: V. Verin, MD, Cardiology Center, University Hospital, 1211 Geneva 14, Switzerland. E-mail vitali.verin{at}hcuge.ch

Abstract

Background Vessel wall responses to percutaneous transluminal coronary angioplasty include neointimal proliferation and arterial remodeling. The contraction of a collagen gel is a good in vitro model of wound repair and vascular remodeling. Because irradiation is an important new therapeutic modality capable of preventing restenosis, the purpose of this study was to evaluate the effect of irradiation on the contraction of a collagen gel by smooth muscle cells (SMCs), on SMCs viability, and on DNA synthesis.

Methods We studied the effect of different doses of gamma-irradiation (0 [control], 6, 12, and 18 Gy) on the contraction of a collagen gel seeded with SMCs (calf carotid arteries) during a period of 15 days.

Results Maximal gel diameter reduction (from 35 to 6.8 mm, ±0.5 mm in control) was markedly inhibited in the 6-, 12-, and 18-Gy groups (35 to 13.7 mm, ±0.8 mm; 35 to 15.5 mm, ±0.9 mm; and 35 to 16.1 mm, ±0.9 mm, respectively; P<0.0001). The irradiated gels showed a dose-dependent reduction in the SMC proliferation rate (P<0.0001) and an increase in the number of nonviable SMCs (P<0.002) 15 days after irradiation.

Conclusions Gamma-irradiation produces a significant dose-dependent inhibition of the contraction of collagen gels seeded with arterial SMCs. This effect is related to a significant decrease in SMC viability and a decrease in SMC proliferation rate. These findings shed light on mechanisms whereby irradiation may positively affect arterial remodeling after percutaneous transluminal coronary angioplasties.

Keywords
  • Restenosis
  • remodeling
  • irradiation
  • smooth muscle cells
  • collagen gels

Statistics from Altmetric.com

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.