Effect of intracerebroventricular infusion of insulin on glucose-dependent insulinotropic peptide in dogs.
Title | Effect of intracerebroventricular infusion of insulin on glucose-dependent insulinotropic peptide in dogs. |
Publication Type | Journal Article |
Year of Publication | 2009 |
Authors | Yavropoulou, M. P., Kotsa K., Anastasiou O., O'Dorisio T. M., Pappas T. N., & Yovos J. G. |
Journal | Neurosci Lett |
Volume | 460 |
Issue | 2 |
Pagination | 148-51 |
Date Published | 2009 Aug 28 |
ISSN | 1872-7972 |
Keywords | Animals, Blood Glucose, Dogs, Drug Administration Routes, Gastric Inhibitory Polypeptide, Gene Expression Regulation, Glucose, Hypoglycemic Agents, Injections, Intraventricular, Insulin, Sweetening Agents, Time Factors |
Abstract | UNLABELLED: Glucose-dependent insulinotropic polypeptide (GIP), is an incretin with important role in glucose homeostasis and energy conservation. Thus far, the neural/hormonal mechanisms involved in the regulation of GIP secretion, have not yet been fully elucidated. The aim of this study was to evaluate a possible effect of intracerebroventricular administration of insulin in a centrally mediated regulation of GIP.METHODS: Twenty-four adult dogs were used in this study. In group 1 the animals received a bolus icv infusion of regular insulin in a total volume of 50 microl or an equivalent amount of artificial cerebrospinal fluid (aCSF). In group 2 the animals received a continuous icv infusion of insulin or aCSF over a 3-h period. In group 3 the experiment of group 2 was repeated with a simultaneous intraduodenal infusion of a glucose load through the Mann-Bollman fistula. Blood samples were taken from cannulation of a hind limb vein at -15, 0, 5, 10, 15, 30, 45, 60, 90, 120, 150 and 180 min after infusions. Plasma levels of glucose, insulin and GIP were assayed.RESULTS: Insulin levels were increased significantly in group 2 and 3 while GIP secretion was partly inhibited after icv administration of insulin and intraduodenal administration of glucose in the 3rd group.CONCLUSIONS: It is suggested that the hypothalamic insulin signaling contributes to plasma insulin levels and possibly exerts a negative regulation of GIP secretion after glucose load. |
DOI | 10.1016/j.neulet.2009.05.052 |
Alternate Journal | Neurosci. Lett. |
PubMed ID | 19477229 |