Goblet cells (GCs) and endocrine cells (ECs) play an important role in intestine physiology, and few studies currently exist for Amazonian fishes. This study aimed to quantify the distribution of GCs and ECs producing cholecystokinin‐8 and neuropeptide Y, assessed by mucin histochemistry and peptides immunohistochemistry, in the intestine of two Amazonian species with different feeding habits Tambaqui (Colossosoma macropomum) and hybrid catfish (Pseudoplatystoma reticulatum × Leiarius marmoratus), an omnivore and carnivore, respectively. A systematic literature review correlating feeding habit and GC and EC distribution was also included to contribute to the comparative study. The results of this study provided novel information about the gut cells of Tambaqui and hybrid catfish. Both, GCs and ECs can be found sweeping the entire intestine of Tambaqui and hybrid catfish although the cells can be more concentrated in certain segments. The GCs and ECs in Tambaqui were more uniformly distributed in the midgut segments (T1, T2, and T3). Unlike, in hybrid catfish GCs were more concentrated in the hindgut (C4) and ECs mainly in the two midgut segments (C1 and C2) of hybrid catfish. Based on the comparison between Tambaqui, hybrid catfish, and other fishes in the literature review, we suggest that cell distribution can be partially explained by feeding habits, carnivorous vs. omnivorous.

中文翻译：

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肠道中杯状细胞和内分泌细胞的分布：亚马逊淡水 Tambaqui 和杂交鲶鱼的比较研究

杯状细胞 (GCs) 和内分泌细胞 (ECs) 在肠道生理学中发挥重要作用，目前对亚马逊鱼类的研究很少。本研究旨在量化产生胆囊收缩素 8 和神经肽 Y 的 GCs 和 ECs 的分布，通过粘蛋白组织化学和肽免疫组织化学评估，在两种具有不同摄食习惯的亚马逊物种 Tambaqui (Colossosoma macropomum) 和杂交鲶鱼 (Pseudoplatystoma reticulatum × Leiarius marmoratus），分别是杂食动物和肉食动物。还包括与摄食习惯和 GC 和 EC 分布相关的系统文献综述，以促进比较研究。这项研究的结果提供了有关 Tambaqui 和杂交鲶鱼肠道细胞的新信息。两个都，可以发现 GCs 和 ECs 遍及 Tambaqui 和杂交鲶鱼的整个肠道，尽管细胞可以更集中在某些部分。Tambaqui 的 GCs 和 ECs 更均匀地分布在中肠段（T1、T2 和 T3）。不同的是，在杂交鲶鱼中，GCs 更集中在后肠 (C4) 和 ECs 中，主要位于杂交鲶鱼的两个中肠段 (C1 和 C2)。根据文献综述中 Tambaqui、杂交鲶鱼和其他鱼类之间的比较，我们认为细胞分布可以部分由食性、肉食性和杂食性来解释。杂交鲶鱼 GCs 更集中在后肠 (C4) 和 ECs 主要在杂交鲶鱼的两个中肠段 (C1 和 C2)。根据文献综述中 Tambaqui、杂交鲶鱼和其他鱼类之间的比较，我们认为细胞分布可以通过食性、肉食性和杂食性来部分解释。杂交鲶鱼 GCs 更集中在后肠 (C4) 和 ECs 主要在杂交鲶鱼的两个中肠段 (C1 和 C2)。根据文献综述中 Tambaqui、杂交鲶鱼和其他鱼类之间的比较，我们认为细胞分布可以部分由食性、肉食性和杂食性来解释。