Short-term intra-arterial infusion of monocyte chemoattractant protein-1 results in sustained collateral artery growth

Monocyte chemoattractant protein-1 (MCP-1) is a stimulator of collateral artery growth and has been shown to increase collateral artery conductance in rabbits and pigs. The minimal infusion duration and the minimally effective dose of MCP-1 are currently unknown, as is the sustainability of the therapeutic effect over a longer observation period than tested before. MCP-1 was infused intra-arterially in pigs after unilateral femoral artery occlusion in different doses and infusion durations between 2 hours and 2 weeks. Two weeks after ligation, arterial conductance under maximal vasodilatation was measured. The long-term efficacy was investigated in 2 additional groups of animals after 6 weeks. Infusion with 2 µg/min of MCP-1 for 6 hours was sufficient to double arterial conductance, and arterial conductance after 6 weeks was still significantly increased.