Drug delivery of anti-restenosis agent by 40 - 60°C heating to porcine aortic smooth muscle cells in vitro.

We investigated the uptake of anti-restenosis agent in vascular smooth muscle cells with heating observing the fluorescence intensity of Oregon green labeled paclitaxel in vitro. The heating temperature to porcine aortic smooth muscle cells was varied from 40 to 60°C in 5 s in order to simulate laser-mediated short-duration heating balloon. The cells were contacted with the agent from 1 to 30 min in 37°C after the heating. We measured the agent uptake characteristics on agent concentration and duration in 37°C as a reference. The uptake of the agent in the cells increased with increasing of both the concentration around the cells and contact duration in the case of 37°C. When the cells were heated with 40°C in 5 s and then contacted with the agent in 30 minutes, the uptake of the agent in the cells significantly increased. The uptake of the agent with 50°C or 60°C in 5 s did not show any increasing. We prospected that 40°C heating to the smooth muscle cells would promote the agent uptake ability of the cells because of homeostasis of the cells.