Quantitative immunohistochemical analysis of duodenal ghrelin cells after sleeve gastrectomy in Wistar rats.

PURPOSE: Sleeve gastrectomy (SG) removes substantial part of the gastric mucosa, which produces ghrelin. This reduction is expected to force other organs, such as the duodenum, to compensate by increasing the number of ghrelin-producing cells. The purpose of this study was to evaluate whether this response occurs. METHODS: Twelve adult male, Wistar rats underwent SG and were reoperated 30 or 60 days after the initial surgery. During the second surgery, a segment of the duodenum was resected to count ghrelin cells using immunohistochemistry. In six animals, SG was not performed, and the duodenal segment served as a control for ghrelin cell counts. The ghrelin cell index (GCI), which is the number of ghrelin cells divided by the number of villi in each segment, was measured and used in statistical analysis by one-way analysis of variance (ANOVA). RESULTS: There were increases in the absolute numbers of cells 30 and 60 days after SG, but statistical analysis by ANOVA showed no significant difference between the groups. CONCLUSION: A compensatory increase in the number of duodenal immunopositive ghrelin cells did not occur as a response to sleeve gastrectomy.

Quantitative immunohistochemical analysis of duodenal ghrelin cells after sleeve gastrectomy in Wistar rats / Análise imunoistoquímica quantitativa das células de grelina duodenais após gastrectomia vertical em ratos Wistar

PURPOSE: Sleeve gastrectomy (SG) removes substantial part of the gastric mucosa, which produces ghrelin. This reduction is expected to force other organs, such as the duodenum, to compensate by increasing the number of ghrelin-producing cells. The purpose of this study was to evaluate whether this response occurs. METHODS: Twelve adult male, Wistar rats underwent SG and were reoperated 30 or 60 days after the initial surgery. During the second surgery, a segment of the duodenum was resected to count ghrelin cells using immunohistochemistry. In six animals, SG was not performed, and the duodenal segment served as a control for ghrelin cell counts. The ghrelin cell index (GCI), which is the number of ghrelin cells divided by the number of villi in each segment, was measured and used in statistical analysis by one-way analysis of variance (ANOVA). RESULTS:There were increases in the absolute numbers of cells 30 and 60 days after SG, but statistical analysis by ANOVA showed no significant difference between the groups. CONCLUSION: A compensatory increase in the number of duodenal immunopositive ghrelin cells did not occur as a response to sleeve gastrectomy.

OBJETIVO: A gastrectomia vertical (GV) remove a maior parte das células produtoras de grelina. Esta redução poderia induzir o duodeno a produzir mais células de grelina de forma compensadora. O objetivo deste trabalho foi estudar se esta compensação ocorre. MÉTODOS: Doze ratos Wistar, machos, foram submetidos à GV e reoperados 30 e 60 dias depois (grupos 30D e 60D) quando um segmento de duodeno foi ressecado para contagem de células de grelina por imunoistoquímica. Em seis animais não foi realizada a GV e um segmento de duodeno foi ressecado para contagem de células de grelina por imunoistoquímica (grupo controle). O índice de células de grelina (ICG), que é o número de células imunopositivas para grelina dividido pelo número de vilosidades do segmento foi calculado e utilizado na análise estatística pelo teste da análise de variância (ANOVA). RESULTADOS: Houve aumento no número absoluto de células 30 e 60 dias depois da gastrectomia vertical, mas a análise estatística por ANOVA não mostrou diferenças significantes entre os grupos. CONCLUSÃO: Não foi observado aumento compensatório no número de células de grelina duodenais após a gastroplastia vertical.