Efeitos da desnervação intrínseca do jejuno após enterectomia extensa na síndrome do intestino curto em ratos

Article (PDF Available)inActa Cirurgica Brasileira 21(1) · February 2006with 64 Reads
DOI: 10.1590/S0102-86502006000100010
Abstract
OBJETIVO: Investigar em ratos Wistar as respostas adaptativas da mucosa em conseqüência da desnervação intrínseca do jejuno após ressecção intestinal extensa. MÉTODOS: Utilizaram-se 30 ratos distribuídos em três grupos segundo o procedimento realizado: C (controle), R (ressecção intestinal) e D (ressecção intestinal e desnervação intrínseca do jejuno). Posteriormente foi avaliado o ganho de peso e realizado estudos morfométrico da mucosa intestinal. RESULTADOS: Os animais do grupo D apresentaram ganho ponderal consideravelmente maior do que os do grupo R (D=312,2?21g e R=196,7?36,2g). A contagem neuronal mostrou diminuição na população de neurônios mientéricos no grupo D (344,8?34,8 neurônios/mm de jejuno) em relação aos outros grupos (R=909,0?55,5 e C=898,5?73,3). A área do epitélio da mucosa jejunal foi maior no grupo D (10,8?4,3mm²) em comparação aos grupos R (7,3?3,9mm²) e C (5,8?3,0mm²). O índice de proliferação celular epitelial da mucosa foi maior no grupo D (48,7%), em relação aos grupos R (31,9%) e C (23,6%). CONCLUSÕES: O modelo experimental mostrou-se eficaz em melhorar o ganho ponderal dos animais submetidos à ressecção intestinal extensa, provocando intensificação da resposta hiperplásica da mucosa, a qual provavelmente levou a aumento da superfície de absorção de nutrientes. Abrem-se boas perspectivas para novas abordagens cirúrgicas para a síndrome do intestino curto.
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