Summary
The intestinal epithelium ofT. suis is composed of metabolically active cells with a gradient of activity which intensifies towards the basal labyrinth. This is reflected by the distribution of hydrolytic enzymes such as acid phosphatase, non-specific esterase and β-D-glucosidase. It is suggested that these enzymes are concerned with the cells' own metabolism and that they may be closely associated with the extensive membrane infoldings which characterise the basal regions of the cells. These infolds together with the elongate, parallel mitochondria present an arrangement typical of cells with an osmoregulatory function.
The brush border is composed of microvilli with tiny pinocytic invaginations frequently visible at their bases. Pinocytic vesicles are also visible in the apical cytoplasm. Materials selectively adsorbed on to the glycocalyx covering each microvillus may thus be absorbed by endocytosis. Preliminary hydrolysis of nutrients, e.g. mucopolysaccharides and/or mucoproteins may be facilitated by β-D-glucosidase and LAP localized in the microvillar layer.
In certain cells of the mid-gut region there is an accumulation of waste material as calcareous concretions. Evidence obtained from fine structure studies indicates that the latter are eliminated via apical cytoplasmic extrusions into the lumen. Such a mechanism for the removal of metabolic waste by the gut cells could be of the utmost significance in the trichuroids since they do not possess a conventional exeretory system.
The distribution of RNA, GER, Golgi vesicles and secretory granules suggests that the cells are capable of some synthetic and secretory activities. In addition the presence of numerous lipid droplets and glycogen granules suggests that the intestinal epithelium is a storage centre of food reserves.
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Jenkins, T. Histochemical and fine structure observations of the intestinal epithelium ofTrichuris suis (Nematoda: Trichuroidea). Z. F. Parasitenkunde 42, 165–183 (1973). https://doi.org/10.1007/BF02482635
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DOI: https://doi.org/10.1007/BF02482635