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)

The results presented show striking differences in the response of the exocrine pancreas to fasting in suckling versus adult rats. In adult rats, fasting led to an increase in lipase to amylase ratio with a particularly sharp decrease in amylase concentrations, a generalized decrease in total protein, amylase, trypsinogen and lipase contents, and a decrease in responsiveness of the pancreatic acini to optimal and supraoptimal concentrations of secretagogues in vitro. In 15 day old pups, however, fasting led to an increase in total amylase, trypsin and lipase and a maintenance of the total protein content in their pancreases. Further, no decrease in responsiveness of their pancreatic acini to secretagogue stimulation is observed at the concentrations studied. The difference in the behavior of the exocrine pancreas during fasting can be partly explained by the changing pattern of their responses to hormonal stimulation, particularly that of corticosterone and cholecystokinin during various stages of development. Fasting led to an increase in corticosterone and presumable decrease in cholecystokinin. The pancreas of the suckling rat is very sensitive to the induction effect of corticosterone while that of the adult rats is relatively insensitive. Conversely, the pancreas of the adult rats is sensitive to the trophic effect of cholecystokinin while that of the suckling rat has the opposite reaction. The combination of these and other factors then resulted in an entirely different profile of the responses of the exocrine pancreas to fasting. Recent studies in our laboratory, and that of others, showed that an analogous situation also existed in the small intestine. Fasting of adult rats led to a general decrease in small intestinal enzymes including sucrase and maltase (29) but in suckling rats led to (30,31) increases of sucrase and maltase. Corticosterone again has been shown to be involved (30,31). Further, the small intestinal sucrase of the suckling rats responded to corticosterone by an increase in its level but the same hormone did not seem to control the sucrase concentrations in the small intestine of adult rats (32,33). Thus, both the small intestine and the pancreas responds very differently to fasting presumably mediated through a varying pattern of responses to selective hormonal stimulation, eg in this case, corticosterone. These results strongly suggest the importance of the interaction between environmental influences (fasting in this case) and the stage of development in determining the outcome of ontogenesis.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Response of the pancreas to fasting: adult versus neonates. 620 75

In the present investigation, the authors aimed to evaluate the role of cytokines in intestinal postnatal maturation induced by dietary polyamines. Neonatal rats were administered either saline (8 mumol) orally. Spermine increased interleukin-1 beta (IL-1 beta), IL-6, and TNF-alpha plasma concentration. The maximum concentrations of IL-1 beta, IL-6, and TNF-alpha were, respectively, observed at 4, 4, and 8 h posttreatment. Intraperitoneal (i.p.) injection of IL-1 beta increased the specific activity of sucrase in whole small intestine, whereas the specific activities of maltase and lactase were significantly enhanced only in the jejunum. IL-6 elicited sucrase and increased maltase specific activity in the whole small intestine, but lactase specific activity was not affected. TNF-alpha had no effect on sucrase and maltase specific activity, but a slight augmentation of lactase specific activity was detected in the jejunum. Spermine and spermidine content in the intestine was increased by i.p. injection of IL-1 beta and IL-6. Corticosterone secretion was elevated by single i.p. injection of IL-1 beta, IL-6, or TNF-alpha. These findings suggest that spermine could induce postnatal intestinal development and corticosterone secretion through a cytokine-dependent mechanism.
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PMID:Role of interleukin-1 beta, interleukin-6, and TNF-alpha in intestinal maturation induced by dietary spermine in rats. 922 34