Ten serwis zostanie wyłączony 2025-02-11.
Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 3

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  neurohormonal control
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
1
100%
EN
Ghrelin and leptin are endogenous peptides that have been implicated in the control of food intake, energy homeostasis and body weight gain. Although the stomach is the major source of circulating ghrelin and partly contributes also to plasma leptin, controversy exists over the influence of gastric Helicobacter pylori (Hp) infection on the ghrelin and leptin release. To resolve this controversy, plasma immunoreactive ghrelin and leptin levels were determined in Hp-positive and Hp negative children (N=60) and in adults (N=120) and daily concentrations of these hormones were measured at 2 h intervals before and after meals. Serum levels of ghrelin and leptin as well as gastrin were measured by RIA. Hp status was assessed using 13C-urea breath test (UBT) and serology. Children with negative UBT showed significantly higher basal serum levels of ghrelin and lower concentrations of leptin than those with positive UBT. Adults without Hp infection also showed significantly higher fasting serum levels of ghrelin and lower levels of leptin than those in Hp infected subjects. In adults, especially without Hp infection, plasma levels of ghrelin showed a marked rise before the meal and sudden decrease following the food intake, while plasma leptin did not showed significant meal-related alterations, but in general its level was significantly higher in Hp positive than Hp negative subjects. Serum gastrin concentrations were significantly elevated in both Hp positive children and adults and these levels were significantly lower in Hp negative subjects. We conclude that Hp infection in children and adults causes a marked reduction in plasma levels of ghrelin, while increasing plasma levels of leptin and gastrin. These alterations in plasma levels of gastric originated appetite-controlling hormones in Hp infected children and adults may contribute to the alterations of the appetite and dyspeptic symptoms observed in these subjects.
2
Content available remote Luminal CCK and its neuronal action on exocrine pancreatic secretion
100%
|
|
nr 4
81-94
EN
Gut regulatory peptides are produced by mucosal endocrine cells and released both into the circulation as well as into the gut lumen. Following stimulation the distribution between the circulation and gut lumen changes in favor of the gut lumen. In the blood plasma, the biological half-life of gut regulatory peptides is counted in single minutes due to high aminopeptidase activity and liver extraction. In the gut lumen, however, regulatory peptides retain their biological activity much longer, especially in newborn and young animals. A series of studies was performed in neonatal calves and pigs to explore the role of luminal cholecystokinin (CCK) on the regulation of exocrine pancreatic secretion. In anaesthetized neonatal calves, CCK was secreted into the duodenal lumen, and electrical vagal stimulation increased CCK release into the duodenal lumen but not into the circulating blood. In conscious calves, luminal CCK-8 stimulated pancreatic protein secretion by a neurohormonal mechanism dependent on a duodenal mucosal CCK1 receptor and vagal nerve activity. Immunocytochemistry pointed to an association of mucosal CCK1 and CCK2 receptors with neuronal components in the small intestine of neonatal calves. Experiments in calves and pigs with CCK-8 infusions into the duodenal branches of the right gastroepiploic artery confirmed the results of luminal CCK-8 and questioned the physiological relevance of a direct mechanism of CCK on the pancreatic acini.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.