CD rats as an animal model in the experimental study of laparoscopic hernia repair.

PURPOSE: The aim of this study was to evaluate the technical feasibility and efficacy of a sutureless laparoscopic hernia repair in a small animal model. The objective was to occlude the processus vaginalis with biocompatible fleece and/or fibrin glue as an alternative to suturing. METHODS: Sixty-three male CD rats were randomly assigned to one of three groups. In group A (n=21), the internal inguinal ring was filled with 0.5 ml fibrin glue. The second group (B, n=21) also received fibrin glue, and a biocompatible fleece was placed on top. The third group consisted of control animals (C, n=21). Eleven rats in each group underwent laparoscopic surgery. The remaining rats were operated using an open technique, and the paraductal lipomas were resected in addition to inguinal ring closure. RESULTS: Complete closure of the internal hernia ring was not achieved in any of the rats, neither in the laparoscopic group nor in the open group or the control group. The paraductal lipoma grew back to its normal size, although resection of the lipoma was performed during the first procedure. CONCLUSION: The physiology of paraductal lipomas in this animal appears to make it an inadequate model for the study of laparoscopic inguinal hernia repair.

Elevated endothelin levels in patients with hyperlipoproteinemia.

We determined lipoproteins, apolipoproteins, and endothelin in 98 patients (58 female and 40 male, age 18-72 years) with hyperlipidemia (plasma cholesterol > 2.5 g/l and/or triglycerides > 2.0 g/l) and in 50 healthy subjects (20 female, 30 male, age 19-68 years). In patients with hyperlipidemia endothelin levels were elevated compared to healthy controls. Patients with plasma cholesterol above 2.5 g/l had higher endothelin and lipoprotein(a) concentrations than patients with plasma cholesterol levels less than 2.5 g/l. A positive correlation was found between the concentrations of endothelin and apolipoprotein B (r = 0.2137; P < 0.013). Smoking patients with lipoprotein (a) above 300 mg/l had higher endothelin levels than both nonsmoking patients with lipoprotein (a) above 300 mg/l and smokers with normal lipoprotein(a). In smokers endothelin correlated positively with Lp(a) (r = 0.709; P < 0.01). No correlation was found between endothelin and triglycerides nor between endothelin and age or sex. The results suggest that the vasoconstrictor endothelin contributes to the increased vasal tone in hyperlipidemia. Because endothelin also has mitogenic properties, it may play a relevant role in the development of premature atherosclerosis in patients with hyperlipidemia.