Papel da óxido nítrico sintase na etiopatogenia da estenose hipertrófica do piloro na infância

OBJECTIVE: To experimentally reproduce, in rats, the findings corresponding to the histopathology of infantile hypertrophic pyloric stenosis (IHSP), using nitric oxide synthase (NOS) inhibitor (L-NAME). METHODS: L-NAME was administered to pregnant rats (L-NAME group), from the 14th gestational day on in order to reproduce the model of NOS inhibition in the production of IHSP. This group was then compared to control animals. After birth, all the animals in the L-NAME group were maintained under NOS inhibition until the 42nd day of life, when they were sacrificed. The control animals, which did not receive any kind of drug, were also sacrificed on the 42nd day of life. The animals and their internal organs were analyzed and weighed. The pyloric region was technically prepared and observed through light microscopy. RESULTS: The L-NAME group presented lower body and intestinal weight and higher gastric weight than the control group. Light microscopy revealed hypertrophy of the circular smooth muscle layer of the pyloric muscle in L-NAME animals. Conclusions: This work reproduced an experimental model of an IHSP study, confirming the effect of NOS blockade on the pyloric musculature. CONCLUSIONS: this work reproduced an experimental model of an IHSP study, confirming the effect of NOS blockade on the pyloricmusculature.