Inducible nitric oxide synthase expression in human vein grafts

Area of Science:

• Vascular Biology
• Molecular Biology
• Surgical Research

Background:

• Intimal hyperplasia (IH) limits vascular reconstructive procedure patency.
• Nitric oxide (NO) may inhibit IH development.
• Inducible nitric oxide synthase (iNOS) produces NO, but its role in human vein grafts is unclear.

Purpose of the Study:

• To investigate iNOS gene expression in human aortocoronary vein grafts (ACVG) and infrainguinal vein grafts (IVG).

Main Methods:

• Quantitative reverse transcription-polymerase chain reaction (RT-PCR) was used to measure iNOS gene expression.
• Samples from ACVG (n=5), IVG (n=5), and control saphenous vein (SV; n=4) were analyzed.
• Glyceraldehyde-3-phosphate-dehydrogenase (GAPDH) served as the internal control.

Main Results:

• iNOS gene expression was significantly higher in ACVG (0.049) compared to IVG (0.019) and normal SV (0.011) (P < 0.05).
• No significant difference in iNOS expression was observed between normal SV and IVG.
• Sequencing confirmed 84% homology of the amplified gene product with the human sequence.

Conclusions:

• iNOS is expressed in human vein bypass grafts.
• ACVGs exhibit significantly elevated iNOS expression compared to IVGs and normal SV.
• Targeting iNOS expression could offer therapeutic strategies against IH in vein grafts.