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)

Studies of intestinal enzyme development and regulation relevant to the human infant require an animal model with a rate of maturation similar to that of the human infant. Hanford miniature pigs were weaned at 3 days of age to a standard swine weaning formula. At 1, 2, 3, 4, 5, and 6 wk of age, duodenal jejunal, and ileal segments were analyzed for protein content and lactase, sucrase, maltase, glucoamylase, and acid beta-galactosidase activities. Protein content of the small intestine changed significantly with age only in the ileum (p less than 0.05). Lactase activity fell significantly with age in all segments of the small intestine (p less than 0.001); activity was highest in the jejunum. Sucrase and maltase activities were present in all segments of the small intestine at 1 wk of age. Sucrase increased significantly (2-fold, p less than 0.02) with age only in the ileum and maltase increased significantly with age in the jejunum (by 50%, p less than 0.05) and the ileum (3-fold, p less than 0.001). Activities were highest in the jejunum. Glucoamylase activity was present at 1 wk of age and showed a small but significant increase with age only in the duodenum (p less than 0.005). Acid beta-galactosidase activity demonstrated small but significant decreases with age in all small intestinal segments. Glucoamylase and acid beta-galactosidase activities were similar in all segments. In the 6-wk-old pigs, activities of all the enzymes tested were similar to those found in young human infants.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The miniature pig as an animal model for the study of intestinal enzyme development. 312 4

The enteric epithelium of suckling rat undergoes dramatic functional and cytokinetic changes (redifferentiation) with maturation. Ileal epithelial maturation was studied in infant rats subjected to 60% proximal enterectomy at age 10 d in an effort to examine redifferentiation mechanisms. Two months after resection the residual ileal remnant was increased in diameter, weight, total protein, and DNA per unit length compared with ileal segments from control littermates that had laparotomy without resection. The residual ileum demonstrated increased sucrase activity per unit length but was indistinguishable from control ileal segments in activity per unit DNA or villus distribution. Lactase activity was negligible in all segments of the residual intestine. Villus height and crypt depth were increased in the residual ileum with slight increases in cell turnover and cell-migration rates. These results show the presence of an intrinsic program for regulation of ileal epithelial maturation and its resistance to alteration by a major stimulus applied before its expression.
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PMID:Maturational patterns of carbohydrases in the ileal remnant of rats after jejunectomy at infancy. 312 30

1. The intestinal disaccharidase activities of a suckling crabeater seal were investigated. 2. Lactase, maltase, isomaltase and cellobiase activities were readily detected but trehalase and sucrase activities were absent. 3. The intestinal homogenates were separated into a soluble (S2) fraction and a particulate brush border (P2) fraction. The lactase activities of the two fractions had different properties corresponding to those of an acid and a neutral beta-galactosidase respectively. Approximately two-thirds of the total lactase activity measured at pH 6.0 was due to the acid beta-galactosidase. 4. The isomaltase and cellobiase activities were found almost exclusively in the particulate fractions but about one third of the maltase activity was in the S2 fraction. This soluble maltase activity appeared to be due to an acid maltase.
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PMID:Intestinal lactase and other disaccharidase activities of a suckling crabeater seal (Lobodon carcinophagus). 313 70

Intestinal morphology and brush border hydrolase activities were determined along the small intestine of young adult (three months, n = 10), mature (12 months, n = 10), and senescent (29 months, n = 15) rats. The intestinal segments of the senescent rats contained higher mucosal mass and protein content (p less than 0.05) compared with the young and mature animals. A significant reduction of villus height and crypt depth (p less than 0.05) was found in the proximal intestine during aging. A 35% increase in villus height (p less than 0.05) without changes in crypt depth, was observed in the distal ileum in senescent rats. The activities of sucrase and isomaltase were significantly increased during aging in the duodenum and jejunum (p less than 0.05). Lactase and aminopeptidase activities which showed only minor changes between young and mature animals were significantly enhanced in senescent animals (p less than 0.05) with aminopeptidase exhibiting a three-fold increase in activity in the proximal ileum. The results when combined with those of previous studies suggest that in the aged animal, the increased level of intestinal hydrolase activities may be the consequence of prolonged cellular maturation along the villi in the proximal intestine, and of adaptation to increased concentrations of intraluminal substrates in the distal intestine.
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PMID:Age related increase of brush border enzyme activities along the small intestine. 320 13

The interactive effects of lima bean trypsin inhibitor (TI), hemagglutinin (Hgg) and cyanide (CN) when fed at the same degree of activity as found in the raw lima bean (RLB) were assessed in weanling rats using hepatic glutamate dehydrogenase (GLDH), isocitrate dehydrogenase (ICDH), ornithine carbamoyltransferase (OCT) and intestinal disaccharidases activities as the response criteria. Whereas RLB significantly (P less than 0.05) increased hepatic GLDH and decreased ICDH activities respectively, dietary CN, TI and Hgg whether acting individually or jointly had no significant influence on GLDH. Only the CN-containing diets significantly (P less than 0.05) elevated ICDH activity when compared with the control. Raw lima bean significantly (P less than 0.05) depressed OCT activity while neither the individual nor collective effects of these factors were significant. Dietary CN + TI + Hgg interaction depressed maltase activity to approximately the same extent as RLB in all the intestinal regions. These factors had neither individual nor collective effects on sucrase in the small intestine. Lactase activity in the small intestine was influenced only by the RLB diet, while CN + Hgg, and CN + TI + Hgg dietary combinations induced significant (P less than 0.05) elevations in the activities of cellobiase when compared with the control. Although synergism of action is indicated in a number of instances, it is suggested that these factors may need to combine with others within the bean, perhaps synergistically, to elicit comparable anti-nutritional influences as the RLB.
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PMID:The interactive effects of lima bean (Phaseolus lunatus) trypsin inhibitor, hemagglutinin and cyanide on some hepatic dehydrogenases, ornithine carbamoyltransferase and intestinal disaccharidases in weanling rats. 324 17

In the present study, we aimed to induce precocious intestinal maturation in neonatal rats by the oral administration of polyamines. Groups of 5 rats received either saline, spermidine (10 mumol daily), or spermine (6 mumol daily) orally on the 12th, 13th, and 14th postnatal days. The rats were killed on the 15th postnatal day. After the small bowel was removed, a 1-cm distal ileal segment was removed for histologic examination and the remaining small bowel tissue was homogenized for further biochemical analysis. Polyamine administration was shown to induce structural and biochemical mucosal changes characteristic of postnatal maturation. Lactase, sucrase, and maltase specific activities (micromoles of substrate hydrolyzed per minute per gram of protein) were 80 +/- 10, 10 +/- 3, and 116 +/- 19 for the saline-treated rats; 51 +/- 7, 34 +/- 2, and 315 +/- 37 for the spermidine-treated rats; and 25 +/- 2, 46 +/- 5, and 419 +/- 63 for the spermine-treated rats, respectively. Similar results were obtained with rats, first treated with spermine (6 mumol) on the 7th postnatal day, receiving spermine (6 mumol) daily as described above and killed on the 10th postnatal day. Dose-response experiments performed as reported above in rats whose treatment began on the 12th postnatal day showed that the maturational effects of orally administered spermine are dose-dependent.
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PMID:Spermine and spermidine induce intestinal maturation in the rat. 337 6

We studied 24 patients with end-stage chronic renal failure not treated with hemodialysis (CRF1) and 16 patients on regular hemodialysis (CRF2), to investigate the digestive, absorptive and morphological aspects of the small intestinal mucosa. Serum d-xylose test and biochemical parameters of absorption (serum calcium and proteins) were determined. Jejunal mucosal biopsies were obtained and tissue homogenates assayed for disaccharidases (sucrase, maltase and lactase) and dipeptidases (glycyl-glycinase, leucyl-glycinase and leucyl-aminopeptidase). Histological changes were classified according to the severity of abnormality and compared with biopsies obtained from control subjects. Serum d-xylose test, calcium and proteins were normal in patients with CRF. Maltase specific activity was higher in CRF1 than in controls (p less than 0.05). Lactase and leucyl-aminopeptidase showed a tendency to decrease in CRF, but this difference did not reach statistical significance. Sucrase, glycyl-glycinase and leucyl-glycinase specific activity in CRF was similar to the control group. Histological changes of the small intestinal mucosa of mild to moderate degree were noted in 68% of patients with CRF vs 36% in control subjects (p less than 0.01). No significant difference was noted in the incidence of absorptive, enzymatic (with the exception of maltase) and histological changes between the two groups of patients with CRF. These changes are not influenced by hemodialysis, a long-term treatment averaging 6 months, they appear to represent primary manifestations of CRF and may be related to the nutritional status of patients with CRF.
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PMID:Small intestinal function and structure in patients with chronic renal failure. 339 24

The aim of the present study was to create clearly documented immediate-type allergy to food protein in the intestine of rats and to study some pathophysiological phenomena induced by challenge with the allergen. To achieve this, rats were sensitized with ovalbumin. A passive cutaneous anaphylaxis reaction to ovalbumin was negative in all controls and positive in all test animals when Bordetella pertussis was used as adjuvant. Sixty minutes after an intravenous injection of 125I-human serum albumin and 45 min after an ovalbumin challenge, given by gavage, the rats were sacrificed. The intestine was removed and sections taken for morphologic studies. The remainder was rinsed, opened, cut into measured segments, weighed, and the radioactivity was measured. Disaccharidases, alkaline phosphatase, and protein were estimated in homogenates of epithelium. Results in both control and test animals showed that radioactivity decreased as one moved distally along the intestine. However, radioactivity was significantly higher (p less than 0.01) in the intestine of test animals than in controls. Radioactivity in liver, kidney, spleen, and lungs was identical in test and control animals. There was significant reduction in levels of alkaline phosphatase (p varied from less than 0.05 to less than 0.001), maltase (p less than 0.05), and sucrase (p less than 0.05 to less than 0.01). Lactase activity in contrast was significantly raised (p less than 0.05). There was no change in intestinal morphology or in the intestinal mast cell count.
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PMID:The effect of immediate-type gastrointestinal allergic reactions on brush border enzymes and gut morphology in the rat. 392 23

To characterize the mechanisms leading to dietary evoked increases of lactase and sucrase activities by carbohydrates, we performed a quantitative comparison of the effects of lactose and sucrose on the corresponding disaccharidases in the jejunum of 2-month-old rats. For 7-10 days the rats were fed a low-starch (5 cal%), high-fat (73 cal%) diet, and for various periods of time (3-72 h) were given an isocaloric sucrose or lactose (20, 40, or 70 cal%) diet. Lactase and sucrase activities in jejunal homogenates were significantly increased within 3 h after the initial feeding of the sucrose (40 cal%) diet. After 3 h of feeding the sucrose diet, sucrase activity gradually increased and reached its maximum at 24 h, whereas lactase activity did not exhibit further change. Increased intake of sucrose led to an increase of lactase and sucrase activity. Within a range of doses of digestible amounts of lactose, the effect of diet containing lactose on these disaccharidase activities was similar to the effect of the diet containing sucrose. This similarity suggests the important role of the common constituent sugar, i.e., glucose. Further, analyses of response to these disaccharides along the villus-crypt axis revealed that the increase of lactase activity occurs at a more apical and broader locus of cohort of epithelial cells along the height of the villus than that of sucrase, suggesting that different mechanisms are involved in dietary regulation of lactase and sucrase.
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PMID:Dietary regulation of intestinal lactase and sucrase in adult rats: quantitative comparison of effect of lactose and sucrose. 393 60

Frequently, congenital or acquired small intestine (SI) abnormalities in infants lead to inadequate absorption. Gastrin has been suggested as a trophic hormone for SI epithelial cells. We chose to evaluate the effect of gastrin on the function and maturation of developing SI using a rat fetal intestine transplant model. Jejunoileal segments (7-8 cm) obtained from 19 to 20 days gestation fetal rats were implanted subcutaneously in syngeneic adult rats. Two weeks following transplantation the control group (N = 10) was continuously infused with saline and the study group (N = 9) was continuously infused with gastrin-17 (13.5 nM/kg/day) for 14 days. Following the infusion, intestinal maturation and function were evaluated by mucosal DNA concentration, disaccharidase activity, and absorption of [14C]galactose and [14C]glycine. Absorption (microM/cm2 SI) by the control and study groups for galactose was 1.10 +/- 0.18 vs 2.73 +/- 0.25, and for glycine was 1.68 +/- 0.23 vs 2.22 +/- 0.26, respectively. DNA concentration (microgram/mg SI) of the control and study groups was 410 +/- 43 vs 1031 +/- 158, respectively. Lactase and sucrase activity were similar in both groups. Although maltase (microM substrate hydrolyzed/min/g SI) was 13.5 +/- 2.7 for the gastrin group vs 7.9 +/- .9 for the control group, statistical significance was not achieved. Thus, gastrin produced a statistically significant increase in DNA concentration (cell mass) (P less than 0.01). More importantly, to our knowledge, this is the first demonstration that exogenously administered gastrin can increase absorption of carbohydrate (galactose; P less than 0.01) and protein (glycine; P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Enhancement of small intestine function by gastrin. 401 Feb 69


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