Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.2.1.26 (invertase)
4,927 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In a study of changes in digestive enzymes after massive intestinal resection and the mechanisms by which such changes occur, rats were sacrified 4 wk after removal of the proximal two-thirds of the small intestine. Alterations in the mucosal levels of sucrase, enterokinase, and dipeptide hydrolase (L-leucyl-L-alanine substrate) were examined in the light of associated changes in protein. DNA and wet mucosal weight, measured in standardized gut segments from various regions of intestine. Metabolic studies showed that normal growth patterns were reestablished after the operation but significant elevations in stool weight and fecal nitrogen occurred in the second postoperative week, falling towards normal by the 4th wk. In standard gut segments wet weight of mucosa, protein, and DNA rose, especially in distal segments, DNA increasing disproportionately. Mucosal levels of the proximally distributed and membrane-bound enzymes, sucrase and enterokinase, showed similar patterns of change: when enzyme activity was expressed in terms of the total per segment, proximally there were considerable increases in both enzymes, but, expressed in terms of specific activity, that of sucrase fell and that of enterokinase was unaltered. By contrast, the largely soluble and more distally distributed dipeptide hydrolase increased more in distal segments and the increases in total activity were accompanied by lesser increases in specific activity. However, in spite of increases in total activity, enzyme activity per milligram DNA fell by over 50% in postanastomotic segments. Subcellular distribution studies showed no change in the percentage of the total activity which was membrane-bound and zymograms confirmed that no new dipeptide hydrolase had appeared after resection. It is concluded that increases in the segmental totals of various enzymes seen after resection are achieved by disproportinate increases in the number of mucosal cells per segment and that the greatest change in a particular enzyme occurs in the region where the enzyme is normally found in highest concentration.
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PMID:Changes in sucrase, enterokinase, and peptide hydrolase after intestinal resection. The association of cellular hyperplasia and adaptation. 469 57

The activity of intestinal enzymes (dipeptidase, monoglyceride lipase, amylase, invertase) was studied in intestinal mucosa homogenates from different parts of the small intestine in adult rats 24, 48, and 72 hours after a single intraperitoneal administration of ethionine in a dose of 500 mg/kg bw. 24 hours after antimetabolite administration there was a decrease in the abrasion of the small intestinal mucosa. The enzyme-forming function of the small intestine appreciably changed throughout the observation period. The activity of invertase, dipeptidase and amylase decreased. The monoglyceride lipase activity remained unchanged. The pattern of amylase and invertase distribution in the small intestine changed at the expense of inhibition of their activity in the duodenum and rise in the distal part.
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PMID:[Effect of ethionine on intestinal enzymatic activity in adult rats]. 616 9

Rats were made severely uremic with partial nephrectomy (24-hour creatinine clearance 10% of normal). Jejunal dipeptidase activities (substrates: glycyl-L-leucine, L-alanyl-L-proline, and L-methionyl-L-methionine), disaccharidase activities (maltase, sucrase, trehalase, and lactase) and morphology were studied. A highly significant increase in glycyl-L-leucine and L-methionyl-L-methionine dipeptidases was found in uremic rats compared with controls. Proline dipeptidase activities were unaltered. Disaccharidase activities showed a slight increase in sucrase in uremic rats; otherwise no change was found.
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PMID:Small intestinal dipeptidases and disaccharidases in experimental uremia in rats. 677 73

Amylase, alpha- and beta-glucosidase, alpha- and beta-galactosidase, beta-fructosidase, trypsin, aminotripeptidase, leucine-aminopeptidase, prolinase, prolidase glycyl-L-leucine dipeptidase and glygylglycine dipeptidase are present in the 3rd instar larvae of Chilo auricilius.
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PMID:Digestive enzymes in the gut and salivary gland of the larvae of Chilo auricilius Ddgn. 698 21

The activities of microvillus aminopeptidase (microsomal, EC 3.4.11.2), dipeptidyl peptidase IV (EC 3.4.14.-), glycyl-leucine dipeptidase (EC 3.4.13.11), proline dipeptidase (EC 3.4.13.9), sucrase (EC 3.2.1.48) and gamma-glutamyl transpeptidase (EC 2.3.2.2) were measured in peroral intestinal biopsies taken from patients with coeliac disease in the acute phase and in remission. A comparison with the amounts of corresponding activities from a reference group showed that all the measured activities were significantly decreased in the acute phase of the disease. In patients in remission only microvillus aminopeptidase and dipeptidyl dipeptidase IV displayed a substantial depression as compared to the reference group. It is suggested that a primary mucosal digestion defect will result in lack of substrate for other intestinal enzymes. This is a situation comparable to starvation and may explain the variation in the grade of restitution for the different enzymes.
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PMID:Intestinal peptidases and sucrase in coeliac disease. 700 82

The enzyme-excretory and motor functions of the gastrointestinal tract of rats flown for 18.5 days onboard the biosatellite Cosmos-1129 were studied. Immediately postflight, the pepsin synthesis decreased and the dipeptide parietal hydrolysis increased. At R + 6, the activity of the enzymes responsible for the cavitary and parietal hydrolysis of lipids significantly grew and that of the enzymes involved in protein hydrolysis fell. At R + 30, the carbohydrate hydrolysis was inhibited and the activity of lipolytic enzymes enhanced markedly. The amplitude and rhythm of stomach biopotentials were dysbalanced. The so-called immobilization stress of intact rats brought about activation of lipase, monoglyceridyl lipase, dipeptidase and inhibition of amylase and invertase. The immobilization exposure of flight rats caused inhibition of the membrane hydrolysis of proteins and carbohydrates and lack of the pancreatic reaction.
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PMID:[Functional state of the gastrointestinal tract organs in rats after a flight on the Kosmos-1129 biosatellite]. 707 39

The development and distribution of peptidase activity in mucosal homogenates of rat small intestine has been investigated. Substrates used were glycyl-L-leucine (GL), L-seryl-L-methionine (SM), and L-leucyl-glycyl-glycine (LGG). During the first 2 weeks of life there was high peptidase activity toward GL and SM in the distal regions of the small intestine. In the third postnatal week, activity in the distal small intestine toward GL and SM decreased, while activity in the proximal small intestine increased. In contrast, there was no difference in activity toward LGG along the length of the small intestine, nor was there a developmental change. Activity toward all three substrates was not affected by cortisone acetate treatment. However, the classical effect of glucocorticoids on sucrase activity and body weight was observed. All peptidases studied showed maximal activities at neutral pH, indicating that they were not lysosomal in origin. Activity towards GL and SM was predominantly located in the cytosol. It is suggested that these dipeptidase activities play a role in the terminal steps of protein digestion following pinocytosis and lysosomal hydrolysis.
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PMID:Postnatal development of peptidase enzymes in rat small intestine. 718 19

The activities of amylase, total proteases, monoglyceride lipase, glycyl-leucine dipeptidase and sucrase were investigated in mucosa from five consecutive parts of small intestine in blue fox, mink, ferret and rat. In comparison with rats, the activity gradient of carbohydrates and TPA in mucosa of predatory animals was shifted in the distal direction. The distribution of dipeptidase and monoglyceride lipase along the intestine was similar enough in all animals: the first was exemplarily the same all along the gut, while the second slightly decreased in a distal direction.
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PMID:Distribution of digestive enzyme activities along intestine in blue fox, mink, ferret and rat. 755 36

The adaptive modulation hypothesis posits that the expression of digestive proteins should be modulated in response to intake of their respective substrates. A corollary of this hypothesis suggests that dietary flexibility and digestive plasticity should be correlated. We examined these two hypotheses in two granivorous Chilean birds (Zonotrichia capensis and Diuca diuca) that differ in dietary breadth. D. diuca is a strict granivore, whereas Z. capensis also eats insects. In field-caught birds, the activity of the intestinal dipeptidase aminopeptidase-N was positively correlated with intake of insects in Z. capensis but not in D. diuca. This is the first field documentation of modulation of intestinal enzymes by diet in birds. Intestinal maltase and sucrase activities were not correlated with seed (vs. insect) intake in either species. In the laboratory, captive birds of both species exhibited similar modulation of membrane-bound intestinal hydrolases when fed on synthetic diets of contrasting carbohydrate and protein composition. Maltase, sucrase, and aminopeptidase-N activities were significantly higher in birds fed on the carbohydrate-free than those on the carbohydrate-containing diet. Activities of the three enzymes were positively correlated. Therefore, this increase probably resulted from nonspecific increases of all enzymes resulting from intake of the carbohydrate-free diet. Principal components analysis separating the effect of diet on specific and on nonspecific modulation revealed that diet had a strong effect on nonspecific activity of intestinal enzymes in both Z. capensis and D. diuca. Diet also significantly affected aminopeptidase-N activities when the effect of diet on nonspecific modulation was removed. Birds fed on the carbohydrate-free, high-protein diet had significantly higher specific aminopeptidase-N activities than those fed on the carbohydrate-containing diet. Our results cast doubts on the notion that dietary flexibility and the plasticity of the gut's enzymes are necessarily correlated and on the general validity of the adaptive modulation hypothesis.
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PMID:Dietary flexibility and intestinal plasticity in birds: a field and laboratory study. 954 55

The present study examines the effects of severe stress on digestive and resorptive functions of the small intestine. Transverse 20-minute acceleration (+10 Gx) results in an increase of invertase activity, particularly in distal parts of the small intestine. Although the activity of glycyl-l-leucine dipeptidase was changed, the fluctuations were less pronounced than those in invertase activity. Acceleration also produces rise in glucose accumulated in the intestinal mucosa and intensification of active carbohydrate transport. The displacement of the proximodistal gradient of invertase activity and carbohydrate resorption was significant. Dipeptidase and invertase activities in intestinal sacs and in tissue homogenates were depressed following exposure to 15-, 30- and 60-day hypokinetics. In distal parts the invertase activity was increased, and the resorptive function was enhanced. Following exposure to unusual gaseous atmospheres (hypoxic, hypercapnic and hyperoxic) there was an increase in active glucose transport over the entire length of the small intestine. Heat produces a decrease in invertase activity both in intact cells and homogenates. There were no pronounced changes in dipeptidase activity. Transport processes exhibited some variations.
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PMID:Digestive and resorptive function of the small intestine in stressful situation. 1269 Nov 11


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