Iontophoretic application of prostaglandin E₁ for improvement in peripheral microcirculation

Objective: The pharmacological effects of iontophoretically applied prostaglandin E₁ (PGE₁) on the peripheral microcirculation were investigated. Material and method: PGE₁ concentrations permeated through hairless mouse skin iontophoretically were measured by HPLC at hourly intervals. 19 patients with arteriosclerosis obliterans were given PGE₁ (20 μg) iontophoretically on the dorsum of the foot. As a control, normal saline was applied iontophoretically on another day. The increase rate in cutaneous blood flow as measured by laser Doppler flux (LDF) level was investigated. 5 of these 19 patients received PGE₁ (20 μg) solution intravenously on another day. The increase rate in cutaneous blood flow as measured by laser Doppler flux (LDF) level was compared between iontophoresis and intravenous drip infusion. Result: PGE₁ was transported across hairless mouse skin with iontophoresis in a time-dependent manner, while it did not permeate by passive transport. The percent increase in LDF level was significantly higher in the PGE₁ group than in the control group(32.7 ± 20.2% vs. 10.3 ± 15.5%, p.001). The percentual increase in LDF level was significantly higher with iontophoresis than with intravenous drip infusion (43.7 ± 19.5% vs. 11.7 ± 28.3%, p < 0.05). Conclusion: The results indicated that iontophoretically applied PGE₁ was effective in improving the impaired microcirculation due to peripheral arterial occlusive disease. This technique may be useful in managing severely ischemic legs.