Trapidil, an Inhibitor for Phosphodiesterase and Platelet-Derived-Growth Factor, Ameliorates Corrosive Esophageal Burn in Rats

Development of a model of benign esophageal stricture in rats: the optimal concentration of sodium hydroxide for stricture formation

PURPOSE

To investigate the optimal concentration of sodium hydroxide (NaOH) on esophageal stricture formation in rats to establish an animal model of benign esophageal stricture (BES).

METHODS

Corrosive esophageal burn was produced by internal application of different concentrations of NaOH to the distal esophagus in rats. As much as 66 male rats were randomly divided into eight groups: Group A (control, n = 6), Group B (sham-operated group, n = 6), Group C (5% NaOH, n = 8), Group D (10% NaOH, n = 8), Group E (20% NaOH, n = 8), Group F (30% NaOH, n = 10), Group G (40% NaOH, n = 14), and Group H (50% NaOH, n = 6). Surviving rats were killed at 28 days. The survival rate, body weight gain, symptoms, and histopathological changes were assessed.

RESULTS

The mortality rate was high in Groups G and H (73 and 67%). The prevalence of symptoms of BES was 43% in Groups D and E, 50% in Group F, 75% in Group G, and 100% in Group H. Statistically significant stricture formation of the esophagus was observed in Groups F and G. The degree of tissue damage was significantly higher in Groups E, F, and G.

CONCLUSION

A high concentration of NaOH of 30% was required to establish a survivable BES model in rats.

Ischemia-reperfusion injury of rabbit ovary and protective effect of trapidil: an experimental study

We aimed to detect the protective effect of trapidil in ischemia-reperfusion (IR) injury due to ovarian torsion and detorsion. Thirty-two pubertal New Zealand albino rabbits were used. Adnexal torsion was created by rotating the left adnexa including the tubal and ovarian vessels in a 360 degrees clockwise direction. Adnexal detorsion was done by untwisting the adnexa. In the IR group, left oopherectomy was performed after 3 h of adnexal torsion and 3 h of adnexal detorsion. In the study group, a 3-h adnexal torsion was performed and trapidil was administered intraperitoneally as a single dose of 40 mg/kg, 1 h before detorsion. The left oopherectomy was performed after a 3-h adnexal detorsion. In the sham group, sham operation was performed followed by left oopherectomy. In the control group, normal ovarian tissue was evaluated. Catalase, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) levels of ovarian tissue were determined for each group. The values of SOD and GSH-Px activities in the IR group were significantly decreased (P < 0.05). In addition, the MDA level was significantly higher in the IR group (P < 0.01). The trapidil-administered group showed significant increase in the levels of GSH-Px (P < 0.05), catalase (P < 0.05), SOD (P < 0.05), and decreased MDA levels (P < 0.05) compared to those in the IR group. The study has shown that trapidil treatment prevents ischemia induced oxidative damage in the ovarian tissues of rabbits.