Estudo morfológico do intestino de ratos após a criação cirúrgica de esfíncteres artificiais

Abstract

RESUMO: Objetivo: Avaliar as alterações morfológicas ocorridas após à confecção de esfíncteres no intestino delgado de ratos. Método: Foram estudados 30 ratos, Wistar, distribuídos em três grupos de 10 animais. Grupo A, controle, foi retirado um segmento de intestino delgado de 20mm de extensão. Grupo B, foram realizados dois esfíncteres, um a 100mm e outro a 150mm da junção íleocecal. Grupo C, um esfíncter à 100mm da junção íleo-ceco-cólica. Entre 10º e 14º dia os animais do Grupo B e C foram re-operados para a ressecção do segmento intestinal envolvendo os esfíncteres com margem de 10mm proximal e distal. As aferições de peso foram feitas no pré-operatório das duas intervenções. O diâmetro das alças foi computado antes e depois da confecção dos esfíncteres. Nas peças ressecadas dos três grupos foram medidas as alturas das vilosidades dos segmentos pré e pós-esfíncter dos Grupos B e C, segmento intermediário do Grupo B e segmento intestinal do Grupo A. Os dados obtidos foram submetidos à análise estatística do programa SPSS. Resultado: O peso dos animais aumentou nos dois grupos com significância no grupo B. Aumento do diâmetro das alças e a média das alturas das vilosidades foram significante. Conclusão: A confecção dos esfíncteres leva a alterações da camada de vilos e dos diâmetros das alças, semelhantes àquelas que ocorrem na fase de adaptação intestinal após ressecções (Rev. ABSTRACT Background: To evaluate variations in weight and diameter of the bowel rats submitted to small bowel surgical sphincter construction comparing values before and after surgery and to study modifications in the mucosal villus. Method: ThirtyWistar rats were submitted to the study divided in three groups of ten. Group A (control) -a segment of small bowel of 20mm of extension was removed. Group B -two sphincters, one 100mm and another 150mm from the ileocecal junction were done. Group C -a sphincter from 100mm of the ileocecal junction was done. Bowel samples were collected and villosity studies were studied 10 to 14 days after first surgery. Measurements of bowel diameters and weights were compared before and after surgery modifications at the end of the study. Height villus measurements of the segments on pre and post-sphincters on both Groups B and C and between sphincters in Group B and also intestinal segment of the Group A were done. Data were submitted to statistics analysis using SPSS program. Result: Animals weight increased in both groups and in Group B the most. Also, intestine diameter increased and the average of the villus heights was larger. Conclusion: Making intestine sphincters results in alterations of the villus layer and increased bowel diameter, similarly to patients that were submitted to wide bowel resections and are adapted. The animals' weight gain can be understood as improvement of nutrients absorption.

Análise da diversidade da microbiota intestinal de ratos submetidos à ressecção da valva ileocecal e criação de esfíncter artificial

“…The creation of sphincter mechanisms in the small intestine is related to the control of intestinal transit speed, particularly in bowel resections. Studies in rats, dogs and humans has shown that artificial valves slow intestinal transit and promote weight gain after intestinal resections 18,[23][24][25][26] . Besides these results, some described techniques show reduction of colonization of the proximal segments of the small intestine through the identification of bacterial growth by intraluminal collections or stool culture.…”

Morphology of the Digestive Apparatus in <i>Oligoryzomys nigripes</i> (Rodentia, Sigmodontinae)

“…Although these animals are widely distributed throughout the Americas, few studies of this group have been conducted. In contrast with murine species, for which extensive literature is available [7]- [10], for cricetid rodents, the data are sparse. Notably, ecological studies [3]- [5] [11] [12], epidemiological data [13]- [15], and a few developmental studies [16]- [18] have been developed for these taxa.…”