Terazosin blockade of nicotine-induced skin flap necrosis in the rat

Objective: To examine the ability of terazosin hydrochloride to block the decrease in skin flap survival induced by nicotine. Design: A randomized controlled animal trial. Subjects: Ninety-two male Sprague-Dawley rats were randomized to 1 of 5 groups: double-placebo control (n=15), nicotine opposed by oral placebo (n=26), nicotine opposed by subcutaneous placebo (n=16) nicotine opposed by oral terazosin (n=21) and nicotine opposed by subcutaneous terazosin (n=14). Intervention: All rats received 1 mg of nicotine twice daily via subcutaneous injection except for those in the double-placebo control group, which received Saline injections twice daily, for the 6-week study. The terazosin treatment groups received 1.5 mg of terazosin hydrochloride twice daily either orally or subcutaneously while the rest received a saline solution placebo either orally or subcutaneously for the last 4 weeks of the study. At the end of the fifth week, a 4x10-cm, caudally based, dorsal random-pattern flap was elevated and repositioned. The outcome was measured in percentage area of flap survival. Results: The mean (±SEM) area of flap survival for the double-placebo control group was 79%±2%. Nicotine opposed by oral placebo or subcutaneous placebo produced a significant decrease in survival areas (mean [±SEM] area, 73%±2% and 74%±2%, respectively). Nicotine opposed by oral terazosin produced a mean (±SEM) survival area of 81%±2%, which was significantly better than the nicotine opposed by placebo group and similar to the control group (P=.02). Conclusion: Use of oral terazosin elevated flap survival rates to control levels in nicotine-treated rats.