A histochemical and immunohistochemical study of digestive enzymes and hormones during the larval development of the sea bream, Sparus aurata L.
The distribution of different hydrolytic enzymes and the localization of the hormones which regulate glucose metabolism during development of the digestive tract of the sea bream, Sparus aurata L., were studied. The yolk sac contains trypsin, glucose-6-phosphatase, ATPases and acid and alkaline phosphatase activities. Positive insulin, glucagon and somatostatin cells were observed in the pancreas and in the lumen of the intestinal tract during endogenous feeding. From hatching until 3 days later, the digestive tract of sea bream larvae shows no enzymatic activities. During exogenous feeding, the activities of the phosphatases and trypsin generally increase, as do the amounts of the hydrolytic enzymes and trypsin, as well as the pancreatic and intestinal hormones. The enzymatic activities gradually decrease from the anterior part towards the posterior part of the digestive tract.
Sarasquete
M C
MC
Instituto de Ciencias Marinas de Andalucía, Polígono del Río San Pedro, Puerto Real, Cádiz, Spain.
Polo
A
A
Gonzalez de Canales
M L
ML
D000135:Acid Phosphatase / Q000032:analysis; D000251:Adenosine Triphosphatases / Q000032:analysis; D000469:Alkaline Phosphatase / Q000032:analysis; D000818:Animals; D004064:Digestive System / Q000737:chemistry* / Q000201:enzymology / Q000254:growth & development; D005934:Glucagon / Q000032:analysis; D006728:Hormones / Q000032:analysis*; D007328:Insulin / Q000032:analysis; D007814:Larva / Q000737:chemistry / Q000201:enzymology; D008099:Liver / Q000737:chemistry / Q000201:enzymology / Q000254:growth & development; D010179:Pancreas / Q000737:chemistry / Q000201:enzymology / Q000254:growth & development; D010473:Perciformes / Q000254:growth & development*; D010744:Phosphoric Monoester Hydrolases / Q000032:analysis; D013194:Staining and Labeling; D015017:Yolk Sac / Q000737:chemistry / Q000201:enzymology
D006728:Hormones; D007328:Insulin; D005934:Glucagon; D000469:Alkaline Phosphatase; D000135:Acid Phosphatase; D010744:Phosphoric Monoester Hydrolases; D000251:Adenosine Triphosphatases