engleski

Histochemical Distribution of Digestive Enzymes in the Intestine of the Common Two-Banded SeaBream, Diplodus vulgaris, Geoffroy St-Hilaire 1817.

Histochemical localization of non-specific esterase, alkaline and acid phosphatase as well as aminopeptidase in the intestine of free-living common two-banded seabream was investigated. Fish were caught in the vicinity of the town of Zadar (Adriatic see, Croatia). Samples of pyloric caeca and three parts of the intestine proper (anterior, middle and posterior) were used for presentation of non-specific esterases, alkaline and acid phosphatase as well as aminopeptidase. Non-specific esterase activity was found in the cytoplasm of enterocytes in pyloric caeca and in all investigated intestinal segments. The activity was stronger in the anterior and posterior part of the intestine than in the pyloric caeca and middle segment of the intestine. Intestinal alkaline phosphatase was detected in brush border of enterocytes of all investigated intestinal segments. Enzymatic activity gradually decreased in posterior direction. Acid phosphatase activity was observed as fine granular reaction product in the supranuclear region of enterocytes. This activity was almost equal in pyloric caeca, and anterior intestinal segment, while it was stronger in the middle and posterior intestinal segment. Aminopeptidase was present along the intestinal epithelium brush border in the all investigated parts of the digestive tube. The intensity of aminopeptidase increased posteriorly. The possible role of investigated enzymes in intracellular digestion and transport is discussed.

common two-banded seabream; digestive enzyme; histochemistry.

nije evidentirano