Estudo histológico e histométrico das vilosidades e das células caliciformes ileais na ileocistoplastia em ratas

Abstract

24 ratos de WISTAR, fêmeas, OUTB EPM-1, divididas em dois grupos experimentais de 4 e 12 semanas (GE eu e GE II). sofreram ileocitoplastia para estudo da mucosa ileal. Cada rato fêmea era seu próprio controle (GC I e GC II), pela exclusão de segmento ileal de 1,0 cm., no momento zero da operação, justaposto ao segmento ileal pediculado de 2,5 cm., que ampliou a bexiga urinária. Depois do tempo experimental, , as peças operatórias retiradas eram processadas com os controles, para estudo microscópico pelos métodos HE e Alcian Blue (pH 2,5) Orange. A eutanásia era consumada com anestésico. Os resultados histomorfométricos eram comparados por grupos entre experimento e controle e depois suas diferenças por grupos independentes, por meio da análise estatística, que fixou 5% o nível de rejeição da hipótese de nulidade, para os testes aplicados. Há diminuição progressiva do número e altura das vilosidades do GE II em relação ao GE I, e de cada experimento, comparado com seu controle. As células caliciformes ileais (sialomucinas), exibem aumento significante e progressivo de seu número. As alterações encontradas na mucosa ileal da ileocistoplastia, não desencorajam sua indicação.

Tissue quantification of neutral and acid mucins in the mucosa of the colon with and without fecal stream in rats

“…This changes occurs specifically in the transition epithelium around the anastomosis, which is exactly the location most subject to the appearance of neoplasia 9 . Schauffert et al 11 studied by histomorphometry the alterations in the ileal mucosa of rats that were submitted to ileocystoplasty for four and 12 weeks, found atrophy and transitional metaplasia that were associated to increase of goblet cells (producers of sialomucins), more pronounced in the group of 12 weeks. Nevertheless, others authors evaluating the tissue expression of mucins in rats submitted to anastomosis between urinary tract (bladder) and left colon found a significant reduction in the amount of acid and neutral mucins at the anastomotic site 9 .…”

“…It has also been shown that such changes may even precede the development of neoplasia 7,8 . Likewise, changes to mucin synthesis and distribution along the mucosa of colon segments without fecal stream that are used as reservoirs or by-pass for reconstituting the urinary transit have been demonstrated 9,10,11 . This suggests that alterations to the expression of these glycoprotein might, in these patients, be considered to be precursory changes for neoplasm development 9,10 .…”

“…However, the neutral mucins was not evaluated and the quantification of the acids mucins was conducted subjectively and its concentration in the colon epithelium was not quantified using methodology of greater precision. With the advent of computer-assisted image analysis software, it has become possible to precisely determine macroscopic and microscopic changes such as number of goblet cells and the tissue expression of various substances 11,12,13 . With this technology, the neutral and acids mucins expression in the colon mucosa can be quantified, and the possibility of differences in total content between segments with and without fecal stream can be investigated, along with the influence of the duration of intestinal exclusion on the intensity of expression of these glycoprotein's.…”