Pentoxifylline and prostaglandin E1 action on ischemia and reperfusion of small intestine tissue in rats. An immunohistochemical study

PURPOSE: To investigate the action of pentoxifylline (PTX) and prostaglandin E1 (PGE1) on ischemia and reperfusion of small intestine tissue in rats, using immunohistochemical analysis. METHODS: Thirty-five Wistar rats were distributed as follows: group A (n=10): subjected to intestinal ischemia and reperfusion for 60 min, with no drugs; group B (n=10): PTX given during tissue ischemia and reperfusion; group C (n=10): PGE1 given during tissue ischemia and reperfusion; group D (n=5): sham. A segment of the small intestine was excised from each euthanized animal and subjected to immunohistochemical examination. RESULTS: Mean number of cells expressing anti-FAS ligand in the crypts was highest in Group A (78.9 ± 17.3), followed by groups B (16.7 ± 2.8), C (11.3 ± 1.8), and D (2.5 ± 0.9), with very significant differences between groups (p<0.0001). CONCLUSIONS: The use of pentoxifylline or prostaglandin E1 proved beneficial during tissue reperfusion. The immunohistochemical results demonstrated a decrease in apoptotic cells, while protecting other intestinal epithelium cells against death after reperfusion, allowing these cells to renew the epithelial tissue. .

Sulfane sulfur deficiency in malignant cells, increasing the inhibiting action of acetone cyanohydrin in tumor growth

PURPOSE: To demonstrate the irreversible poisoning action of the acetone cyanohydrin (AC) in malignant cells. METHODS: Thirty male Swiss mice were inoculated with 1x10³ Ehrlich tumor (ET) cells. The mice were divided into three groups (n=10): CG (saline); ACG1 (1.864 mg/Kg of AC) and ACG2 (2.796 mg/Kg of AC), treated every 48 hours from day 3 until day 13. On day 15 the mice were euthanized and the number of viable cells in ascites was determined. In the meantime, ET cells were incubated with AC (0.5, 1.0, 2.0 μg/mL). Cell viability and percentage of growth inhibition (PGI) were checked after one, two, three, four, 18 and 24 hours. RESULTS: There was reduction in volume and number of viable cells in ACG1 and ACG2 compared to CG. In ACG1 one of the animals did not present ascites. In ACG2 two mice did not present ascites and in CG none of the mice present ascites. The action of AC was dose and time dependent and there was no significant difference among the three doses. CONCLUSION: The acetone cyanohydrin promoted reduction of the tumor and also prevented tumor development in 20% of the treated animals.

Expression of FAS ligand in the ipsilateral and contralateral testicles of rats subjected to the torsion of the unilateral testicular cord

PURPOSE: To investigate the expression of FAS ligand (FASL) in ipsilateral and contralateral testicles of rats submitted to ischemia/reperfusion. METHODS: Wistar rats (n=21) distributed into groups control (GC), n=5, testicular exposure; ischemia (GI), (n=8), Torsion in the left testicular Cord (TCT) for three hours followed by orchiectomy without distortion and orchietomy of the contralateral testicle after 24 hours; and reperfusion (GR), (n=8), left TCT for 3 hours and distortion and repositioning on the scrotum and bilateral orchiectomy after 24 hours. Quantification of the FASL expression by immune-histochemistry. RESULTS: Statistical analysis showed similarity between GC and GI (p>0.05), differences detected are concentrated on the GR (p<0.05), increase in immunoexpression of FASL in the subgroups Right GR (406.8+-61.5) and Left GR (135.3 +-28.9) with significant predominance in the GR subgroup. CONCLUSION: Ischemia/reperfusion increased the FASL expression significantly in contralateral testicles in GR, in rats.