Gene/Protein
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Symptom
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Enzyme
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Pivot Concepts:
Gene/Protein
Disease
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Drug
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Target Concepts:
Gene/Protein
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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)
Glucocorticoids and thyroxine modulate postnatal intestinal sucrase and lactase activities. Whether changes in enzyme activity are accompanied by changes in enzyme mRNA levels were determined in day 6 rats given thyroxine, cortisone, or thyroxine plus cortisone and killed 3 days later. Cortisone induced precocious expression of jejunal
sucrase
activity which was enhanced when cortisone plus thyroxine was administered;
sucrase
mRNA changed in parallel. Jejunal lactase activity was unaffected by thyroxine and was increased after cortisone, but not after thyroxine plus cortisone. Jejunal lactase mRNA levels increased equally after cortisone or after cortisone plus thyroxine. Thus, cortisone induces coordinated increases in
sucrase
and lactase activities and in corresponding mRNA levels.
Thyroxine
only enhances cortisone induced
sucrase
expression and antagonizes cortisone by depressing lactase activity post-translationally.
...
PMID:Cortisone and thyroxine modulate intestinal lactase and sucrase mRNA levels and activities in the suckling rat. 171 74
The evolution pattern of brush-border digestive hydrolases and their hormonal regulation were studied in the proximal colon of newborn rats. The potentiality of the colon to express a small intestinal enzymatic pattern was also examined in associations made up of colonic endoderm and small intestinal mesenchyme, developed as either intracelomic grafts in 3-day-old chick embryos or as intrarenal grafts in adult rats. A transient increase of lactase- and aminopeptidase-specific activities occurred in the colon from the 19th day of gestation to 14 days after birth, but
sucrase
activity could never be detected. Immunocytochemical studies with antibodies specific for rat lactase, aminopeptidase, and
sucrase
confirmed these results. However, the levels of hydrolase activities were lower in the colon than in the jejunum at the same age.
Thyroxine
or hydrocortisone treatment during the first 4 days postpartum decreased lactase activity by 70 and 30%, respectively, but did not affect aminopeptidase activity. A slight but significant induction of
sucrase
activity was obtained with both hormones. In contrast, in the jejunum, only thyroxine decreased lactase activity with a lesser effect (30%), but both hormones increased aminopeptidase activity and induced the marked well-known appearance of
sucrase
activity. The fetal small intestinal mesenchyme was not able to induce the colonic endoderm to achieve a small intestinal-like differentiation. But the exposure of the developed hybrid intestines to glucocorticoids in organ culture allowed expression of
sucrase
in one-third of the cases. These results demonstrate the presence of brush-border hydrolases in the proximal colon of newborn rats, normally expressed in the small intestine, but never in the adult colon.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Perinatal expression of brush-border hydrolases in rat colon: hormonal and tissue regulations. 267 33
The influence of hydrocortisone (10(-8)--10(-5) M) and thyroxine (10 (-9)--10(-6) M) on intestinal epithelial cell differentiation and proliferation have been studied using explants of suckling mouse jejunum maintained in serum-free organ culture. Hydrocortisone induced the appearance of
sucrase
activity and increased trehalase, glucoamylase, lactase and alkaline phosphatase activities.
Thyroxine
was completely ineffective at all the concentrations used. None of these hormones affected the mitotic activity or the 3H-thymidine incorporation into DNA. These results demonstrate that hydrocortisone but not thyroxine acts directly on intestinal brush border membrane differentiation and that both hormones do not influence the proliferation of the epithelial cells during postnatal development.
...
PMID:Comparative study of the effect of hydrocortisone and thyroxine on suckling mouse small intestine in organ culture. 614 44
In the adult rat, starvation during 48 hours led to a three fold increase of lactase specific activity in the intestinal brush border membranes.
Thyroxine
injection during the three days before death (0.5 micrograms/g daily) inhibited the stimulation of lactase activity induced by starvation without modifying
sucrase
activity whereas hydrocortisone injections (25 micrograms/g daily) or thyroidectomy did not modify the stimulatory effect of starvation on lactase activity. These results suggests a specific hormonal control of intestinal lactase activity in the rat.
...
PMID:Lactase activity is under hormonal control in the intestine of adult rat. 640 6
Imposition of undernutrition during the suckling period considerably enhanced the intestinal uptake of D-glucose and glycine compared to a control group. Brush border
sucrase
, and alkaline phosphatase activities were drastically reduced while lactase and leucine amino peptidase levels were significantly elevated at weaning in nutritionally deprived pups as compared to control animals. Cortisone administration to undernourished rats depressed the uptake of D-glucose but stimulated that of glycine.
Thyroxine
treatment to undernourished animals reduced the uptake of glucose but had no effect on glycine absorption. Brush border
sucrase
and alkaline phosphatase activities were stimulated in cortisone- or thyroxine-injected undernourished rats but lactase activity was depressed under these conditions. Leucine aminopeptidase activity remained unaffected in cortisone- or thyroxine-administered undernourished pups.
...
PMID:Alterations in intestinal function in response to thyroxine and cortisone administration in undernourished rats. 713 57