PURPOSE:To investigate the impact of cafeteria diet on ghrelin expression in rectal tissue and identify the morphologic cell type. METHODS:Twenty-four male Wistar rats were divided into four subgroups of six animals each: RC1 (rat chow 1) and CAF1 (cafeteria diet 1) for a period of 30 days; RC2 (rat chow 2) and CAF2 (cafeteria diet 2) for a period of 60 days. The animal and rectal weight, the number and the type of immunoreactive ghrelin cells were recorded and compared between the subgroups. The statistical study was established by ANOVA and Student's t test. RESULTS:There was no difference in the total of immunoreactive cells (p=0.685) between the subgroups nor between weight and presence or absence of ghrelin expression (p=0.993). All the immunoreactive cells identified were closed-type. CONCLUSION:The cafeteria diet did not have influence on the amount of immunoreactive rectal cells of ghrelin and only one type (closed-type) of immunoreactive cells was expressed in the rectum.

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.

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.