Phenotypic changes of interstitial cells of Cajal after intestinal obstruction in rat model

The objective was to study the effect of mechanical intestinal obstruction in rats on the phenotype of interstitial cells of Cajal (ICC). Healthy Wistar rats were randomly divided into sham-operation group (C), one day obstruction group (M1), two days obstruction group (M2), and three days obstruction group (M3), with 10 rats in each group. The expression of SCF mRNA and c-Kit protein in intestinal tissue was investigated by RT-PCR and immunohistochemistry. Compared with the sham-operation group, the relative expression of SCF mRNA and the expression of c-Kit protein in intestinal tissue were significantly decreased in both obstruction groups. Levels decreased gradually with the prolongation of obstruction time, and significantly decreased on the 3rd day after obstruction (P<0.05). Immunohistochemical staining of the small intestine showed that the number of ICC in the sham-operation group was the highest, and they were gradually decreased with the extension of obstruction time in the M1 to M3 groups. There was a significant difference between groups (P<0.05). Intestinal obstruction caused a decrease in the concentrations of SCF mRNA and c-Kit protein in ICC. With the prolongation of intestinal obstruction, the number of ICCs gradually decreased.

Hypertonic saline and pentoxifylline enhance survival, reducing apoptosis and oxidative stress in a rat model of strangulated closed loop small bowel obstruction

OBJECTIVES: Intestinal obstruction has a high mortality rate when therapeutic treatment is delayed. Resuscitation in intestinal obstruction requires a large volume of fluid, and fluid combinations have been studied. Therefore, we evaluated the effects of hypertonic saline solution (HS) with pentoxifylline (PTX) on apoptosis, oxidative stress and survival rate. METHODS: Wistar rats were subjected to intestinal obstruction and ischemia through a closed loop ligation of the terminal ileum and its vessels. After 24 hours, the necrotic bowel segment was resected, and the animals were randomized into four groups according to the following resuscitation strategies: Ringer's lactate solution (RL) (RL-32 ml/kg); RL+PTX (25 mg/kg); HS+PTX (HS, 7.5%, 4 ml/kg), and no resuscitation (IO-intestinal obstruction and ischemia). Euthanasia was performed 3 hours after resuscitation to obtain kidney and intestine samples. A malondialdehyde (MDA) assay was performed to evaluate oxidative stress, and histochemical analyses (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling [TUNEL], Bcl-2 and Bax) were conducted to evaluate kidney apoptosis. Survival was analyzed with another series of animals that were observed for 15 days. RESULTS: PTX in combination with RL or HS reduced the MDA levels (nmol/mg of protein), as follows: kidney IO=0.42; RL=0.49; RL+PTX=0.31; HS+PTX=0.34 (p<0.05); intestine: IO=0.42; RL=0.48; RL+PTX=0.29; HS+PTX=0.26 (p<0.05). The number of labeled cells for TUNEL and Bax was lower in the HS+PTX group than in the other groups (p<0.05). The Bax/Bcl-2 ratio was lower in the HS+PTX group than in the other groups (p<0.05). The survival rate on the 15th day was higher in the HS+PTX group (77%) than in the RL+PTX group (11%). CONCLUSION: PTX in combination with HS enhanced survival and attenuated oxidative stress and apoptosis. However, when combined with RL, PTX did not reduce apoptosis or mortality.

Carcinoma rectocolónico complicado / Complicated colorectal carcinoma

Se operaron 421 pacientes con carcinoma colorrectal entre 1971 y 1986. De ellos el 19% fueron por complicaciones agudas, 14,9% por obstrucción, 2,63% por obstrucción y perforación, 1,4% perforación y 0,23% por obstrucción y hemorragia copiosa. A pesar del elevado porcentaje de tumores con invasión a otros órganos, metástasis a distancia y carcinosis peritoneal (30,86%), pudo resecarse un 78% de los mismos. En este período dominó la cirugía en un tiempo en la localización derecha y la cirugía en etapas en la izquierda. La cirugía resectiva secundaria se realizó en el 76% de los enfermos con carcinomas localizados en el colon izquierdo y la colostomía se cerró en el 59% de éstos. En la estadificación de Dukes predominó la clase C 45,83%, seguida de la B 29,16%, D 32,61% y A 1,38%. Las complicaciones inmediatas fueron del 48%, destacándose las sépticas, cardiovasculares y respiratorias. La mortalidad postoperatoria inmediata fue del 8,6%, sobrevive a los 5 años de operado el 24,69% de los enfermos y menos de 5 años con un promedio de 30 meses el 12%. El porcentaje de sobrevida a los 5 años fue del 38% para la clase B de Dukes, 24% para la clase C y no hubo sobrevida a los 5 años para la clase D.