[Amount of ampicillin in surgical wound of rat skin].

Abstract

Ampicillin is widely used for the treatment and prevention of infection. When ampicillin is administered for the prevention of postoperative infection, the target tissue is a surgical wound. Since the surgical wound differs from the normal tissue, the distribution of ampicillin into the surgical wound might be affected. Thus, the present investigation was undertaken to compare with the amount of ampicillin in surgical wound and normal tissue. The vascular permeability and water content in the surgical wound were also determined. Wistar strain SPF male rats, 12 weeks old were used. Ampicillin.Na (50 mg/kg) was administered intravenously. Each rat head skin was incised 30 seconds after administration of ampicillin.Na. Specimens of serum, incised skin (surgical wound), and intact skin (normal tissue) were collected at 0.25, 0.50, 0.75, 1.0, 1.5, 2.0, 3.0, 4.0, 6.0 and 8.0 hours after incision. Amount of ampicillin in serum and skins were assayed by a thin layer disc plate method. Vascular permeability was determined by a dye diffusion method. Water content was obtained by subtracting the dry tissue weight from the wet tissue weight. The results are as follows: 1. The amount of ampicillin in serum at 0.25 hours after incision was 78.37 +/- 16.15 micrograms/ml. Ampicillin level was rapidly decreased during 0.25 to 1.0 hours after incision, and then gradually decreased to reach 0.04 +/- 0.02 micrograms/ml at 8.0 hours. 2. The amount of ampicillin in incised skin was significantly higher than that of intact skin during 0.50 to 8.0 hours after incision (t-test, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)