Distribution of glucose-6-phosphatase and 5-nucleotidase in the digestive system of two teleost fishes

Sastry, K.V.; Agrawal, V. P.; Garg, Verandra Kumar

doi:10.1016/s0065-1281(76)80046-3

Cited by 13 publications

(15 citation statements)

References 15 publications

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“…Esterase has also been reported to be present from stomach to rectum in turbot (Munilla- Moran and Stark 1990). It is possible that in the turbot a lipase produced in the intestinal mucosa (Sastry 1974) and more active at higher pH accumulates in the hindgut and rectum with the digesta and exhibits increased activity as a consequence of the alkaline pH found there (Buddington and Doroshov 1986;Borlongan 1990;Munilla-Moran and Stark 1990). The principle products available for absorption following lipolysis of TAGs, namely FFA and MAG, are thought to be fundamentally the same in both mammals and fish (Fange and Grove 1979;Sire et al 1981).…”

Section: Discussionmentioning

confidence: 99%

“…Consequently, lipase activity that are subsequently absorbed in the intestinal wall has been detected in the digestive tract of various of the jejunum (Gurr and Harwood 1991). Almarine fish species (Chesley 1934;Kitamikado and though the teleost pancreas is generally diffuse, fish Tachino 1961 ;Brockerhoff 1966;Sastry 1974; digestive lipases were assumed to be similar to Mukhopadhyay 1977; Olatunde and Ogunbiyi mammalian lipases (Brockerhoff 1966) and this was demonstrated in several species (Brockerhoff and Hoyle 1965;Brockerhoff 1966;Tocher and Sargent 1984). It followed that lipid digestion and absorption were shown to take place primarily in the anterior intestine (Mukhopadhyay 1977;Fange and Grove 1979;Buddington and Doroshov 1986;Das et al 1987;Borlongan 1990).…”

Section: Introductionmentioning

confidence: 99%

“…However, the PUFA of marine lipids are not readily hydrolysed, irrespective of position, by mammalian 1,3 specific pancreatic lipase in vitro (Bottino et al 1967;Chen et al 1990) suggesting that a lipase other than pancreatic lipase is the major lipolytic enzyme in fish . In fact, some teleosts can secrete intestinal mucosal lipase (Sastry 1974;Kapoor et al 1975) that can be active throughout the digestive tract (Munilla-Moran and Stark 1990). Fish lipases can vary in their lipolytic activity showing a combination of positional and fatty acid specificity.…”

Section: Introductionmentioning

confidence: 99%

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Lipid digestion in turbot (Scophthalmus maximus). I: Lipid class and fatty acid composition of digesta from different segments of the digestive tract

Koven

Henderson

Sargent

1994

Fish Physiol Biochem

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The lipid content and lipid composition of digesta from the stomach, foregut, hindgut and rectum of juvenile turbot fed a commercial diet were determined in order to examine the process of lipid digestion in this species. The moisture content of the digesta increased along the digestive tract from 71.5% in the stomach to 89.6% in the rectum. The lipid content of the digesta increased initially from 15.7% of the dry weight in the stomach to 36.1% in the foregut but thereafter decreased through 23.2% in the hindgut to 9.1% in the rectum. The proportion of triacylglycerols (TAG) in the total lipid of the digesta decreased from 63% in the stomach to 17.4% in the rectum whereas that of free fatty acids (FFA) increased from 10016 to 48.9%. The highest proportions of monoacylglycerols (MAG), diacylglycerols (DAG) and most phospholipids were observed in the lipid of the hindgut digesta. In addition, a fall in levels of neutral and phospholipid classes as digesta moved from hindgut to rectum signified absorption.Analysis of the fatty acid composition of the lipid classes TAG, DAG and MAG suggest a polyunsaturated fatty acid specificity for hydrolysis may exist. Saturated, monounsaturated and polyunsaturated fatty acids (PUFA) accounted for 17.9%, 45.4% and 37.0%, respectively of the FFA present in the foregut whereas the corresponding values for the rectum were 32.6%, 51.9% and 16.3%. Overall, the results suggest a PUFA specifity for hydrolysis may exist alongside the positional non-specific lipolytic activity associated with the hindgut regions of the digestive tract of turbot and that PUFA, released by lipolysis are more effectively absorbed from the digesta than monounsaturated and saturated fatty acids.

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Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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Lipid digestion in turbot (Scophthalmus maximus). I: Lipid class and fatty acid composition of digesta from different segments of the digestive tract

Koven

Henderson

Sargent

1994

Fish Physiol Biochem

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“…However, the accentuation associated with the periportal hepatocytes of the trout G-6-Pase was slight when we compared it to that of identically reacted rat liver (Teutsch, 1978(Teutsch, , 1981(Teutsch, , 1984; this study). Sastry et al (1976) reported studies of G-6-Pase localization in livers of a herbivorous fish, Barbus sophore, and an omnivorous fish, Heteropneustes fossilis. In both they stated that G-6-Pase activity was localized in the centrolobular area surrounding the biliary canaliculi and sinusoids.…”

Section: Discussionmentioning

confidence: 99%

“…Hepatocytes, endothelial cells, bile ductular epithelial cells, fat-storing cells, macrophages, circulating blood cells, and exocrine pancreatic cells all occur in teleost liver (Hinton et al, 1984b), but we do not know whether there are subpopulations of hepatocytes based on histochemistry (Novikoff, 1959;Teutsch, 1981), ultrastructure (Schmucker et al, 1978;Kanamura et al, 19841, andor response to specific xenobiotics (Jones and Fawcett, 1966;Baron et al, 1981). Literature on liver of teleosts in general (Hinton and Pool, 1976;Hinton et al, 1984b;Welsch and Storch, 1973;Sastry, 1975;Sastry et al, 1976) and trout in particular (Gingerich et al, 1978;Chapman, 1981;Anderson and Mitchum, 1974) contains @ 1985 ALAN K. LISS, INC numerous instances in which terms derived from the mammalian liver lobule are used. Such usage, without scientific basis in a tubular liver, underscored the need for analysis of functional units in teleost liver.…”

mentioning

confidence: 99%

Functional units in rainbow trout (Salmo gairdneri) liver: I. Arrangement and histochemical properties of hepatocytes

Hampton

McCuskey

et al. 1985

Anat. Rec.

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The architectural arrangement and selected histochemical properties of hepatocytes in the rainbow trout (Salmo gairdneri Richardson) were examined. Light and transmission electron microscopic (TEM) examination following fixation by portal venous perfusion revealed a tubular arrangement of hepatocytes. Lobules, as defined in the adult mammal, were absent. Biliary epithelial cells associated with bile preductules and ductules were a prominent feature of trout liver. Patterns and location of reaction products for glucose-6-phosphatase (G-6-Pase), glucose-6-phosphate dehydrogenase (G-6-PDH), and magnesium-dependent adenosine triphosphatase (ATPase), enzymes preferentially distributed in mammalian liver, were demonstrated in trout liver. A slightly heavier staining pattern for G-6-Pase was seen around presumptive portal venules but all other enzyme reaction patterns were uniform throughout the liver parenchyma. Following ATPase localization, four sizes of biliary passageways (canaliculi, bile preductules, ductules, and ducts) were visualized. Maximum glycogen retention was achieved with freeze-drying and glycolmethacrylate embedding and with this method intense, uniform glycogen staining was observed in all areas of the liver. Companion TEM examinations revealed large depots of glycogen within hepatocytes. The results are important for interpretation and description of the effects of toxic/carcinogenic alteration on trout liver.

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Morphology and lectin‐binding sites of pyloric caeca epithelium in normal and GnRH‐treated Atlantic bluefin tuna (Thunnus thynnus) Linnaeus 1758

Zizza

Desantis

2010

Microscopy Res & Technique

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Mucosal epithelium of pyloric caeca was studied in normal and in GnRH-treated Atlantic bluefin tuna Thunnus thynnus L., using morphological analysis, conventional and lectin glycohistochemistry. The lining epithelium consisted of columnar (absorptive) cells, goblet cells and intraepithelial leucocytes. The epithelium from normal animals was significantly taller than GnRH-treated samples. Conventional histochemistry displayed the same staining pattern in normal and hormone-treated specimens which showed a mixture of neutral and sulphated acidic glycoconjugates in the luminal surface and goblet cells, and neutral glycans in apical granules of enterocytes. Lectin histochemistry revealed a different glycoconjugate pattern in normal and GnRH-treated tunas. In normal specimens the luminal surface expressed sialoglycoconjugates which bound MAL II, SNA, KOH-sialidase-PNA, KOH-sialidase-SBA as well as asialoglycans stained with HPA, SBA, GSA I-B4 , LTA. N-linked glycans were highlighted by Con A and KOH-sialidase-WGA. In GnRH-treated tunas the luminal surface did not react with SNA, SBA and LTA. The columnar cells of normal tunas bound KOH-sialisase-PNA in the apical region, KOH-sialidase-PNA, KOH-sialidase-DBA, HPA, SBA, KOH-sialidase-SBA and KOH-sialidase-WGA in apical granules, GSA I-B₄ and LTA in the supranuclear region. GnRH-treated specimens showed some columnar cells that stained with KOH-sialidase-WGA in the apical granules and with GSA I-B4 in the supranuclear region. The goblet cells of normal animals produced mucins positive to PNA, HPA, KOH-sialidase-DBA, SBA, GSA II. The latter three binding sites lacked in GnRH-treated tunas. The results suggest that the mucosal epithelium of Thunnus thynnus L. pyloric caeca expresses a complex glycan pattern that is affected by GnRH-treatment.

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Distribution of glucose-6-phosphatase and 5-nucleotidase in the digestive system of two teleost fishes

Cited by 13 publications

References 15 publications

Lipid digestion in turbot (Scophthalmus maximus). I: Lipid class and fatty acid composition of digesta from different segments of the digestive tract

Lipid digestion in turbot (Scophthalmus maximus). I: Lipid class and fatty acid composition of digesta from different segments of the digestive tract

Functional units in rainbow trout (Salmo gairdneri) liver: I. Arrangement and histochemical properties of hepatocytes

Morphology and lectin‐binding sites of pyloric caeca epithelium in normal and GnRH‐treated Atlantic bluefin tuna (Thunnus thynnus) Linnaeus 1758

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