RGD Reference Report - Impairment of the insulinotropic effect of gastric inhibitory polypeptide (GIP) in obese and diabetic rats is related to the down-regulation of its pancreatic receptors. - Rat Genome Database

Send us a Message
Submit Data |  Help |  Video Tutorials |  News |  Publications |  Download |  REST API |  Citing RGD |  Contact   
Search RGD Grant Resources Citing RGD About Us Contact Us
Genes Variants Community Projects QTLs Strains Markers Genome Information Ontologies Cell Lines References Download Submit Data
OntoMate (Literature Search) JBrowse (Genome Browser) Synteny Browser (VCMap) Variant Visualizer Multi-Ontology Enrichment (MOET) Gene-Ortholog Location Finder (GOLF) InterViewer (Protein-Protein Interactions) PhenoMiner (Quatitative Phenotypes) Gene Annotator OLGA (Gene List Generator) AllianceMine GViewer (Genome Viewer)
Aging & Age-Related Disease Cancer & Neoplastic Disease Cardiovascular Disease Coronavirus Disease Developmental Disease Diabetes Hematologic Disease Immune & Inflammatory Disease Infectious Disease Liver Disease Neurological Disease Obesity & Metabolic Syndrome Renal Disease Respiratory Disease Sensory Organ Disease
Find Models   new Genetic Models Autism Models Rat PhenoMiner (Quantitative Phenotypes) Chinchilla PhenoMiner Expected Ranges (Quantitative Phenotype) PhenoMiner Term Comparison Hybrid Rat Diversity Panel Phenotypes Phenotypes in Other Animal Models Animal Husbandry Strain Medical Records Phylogenetics Strain Availability Calendar Rats 101 Submissions Photo Archive
Pathways
Rat Community Forum Directory of Rat Laboratories Video Tutorials News RGD Publications RGD Presentations Archive Nomenclature Guidelines Resource Links Laboratory Resources Employment Resources

Impairment of the insulinotropic effect of gastric inhibitory polypeptide (GIP) in obese and diabetic rats is related to the down-regulation of its pancreatic receptors.

Authors: Younan, SM  Rashed, LA 
Citation: Younan SM and Rashed LA, Gen Physiol Biophys. 2007 Sep;26(3):181-93.
RGD ID: 2312547
Pubmed: PMID:18063845   (View Abstract at PubMed)

The association of obesity with type 2 diabetes mellitus has been recognized for years. In type 2 diabetes, there is a possibility that an important part of the impaired insulin secretion is due to the gastric inhibitory polypeptide (GIP) hormone. This study investigated changes that occur in the pancreatic GIP receptors' (GIP-Rs) expression and in GIP secretion in obese and type 2 diabetic rats and its relation to plasma glucose and insulin levels during oral glucose tolerance test (OGTT) compared to control rats. During the first 20 min of the OGTT, both the obese and the diabetic rats had a significant increase in the glucose excursion and a significant decrease in early-insulin secretion compared to the control group, with more prominent changes in the diabetic group. The obese rats had a significant increase in fasting GIP level and in the incremental change of GIP from 0 to 20 min (GIP Delta 0-20: 60.1 + or - 6.66 pmol/l) compared to that of the control (33.96 + or - 4.69 pmol/l) and the diabetic (29.34 + or - 2.62 pmol/l) group, which were not significantly different from each other. However, there was a significant decrease in GIP-Rs expression in both the obese (88.07 + or - 10.36 microg/ml) and diabetic (87.51 + or - 4.72 microg/ml) groups compared to the control group (120.35 + or - 8.06 microg/ml). During the second hour of the OGTT, plasma GIP was decreasing in all groups, however, the obese group had a significant hyperinsulinemia compared to the other two groups. Moreover, the diabetic group had a significantly lower plasma insulin level until the 90 min interval and thereafter it showed a non-significant difference compared to the control group. In conclusion, both obese and diabetic rats had an impaired early-phase insulinotropic effect of GIP due to impaired gene expression of GIP-Rs which could be a potential target to prevent transition of obesity to diabetes and to improve insulin secretion in the latter.



RGD Manual Disease Annotations    Click to see Annotation Detail View
Object SymbolSpeciesTermQualifierEvidenceWithNotesSourceOriginal Reference(s)
GIPHumanobesity  ISOGip (Rattus norvegicus)protein:increased expression:plasma (rat)RGD 
GipRatobesity  IEP protein:increased expression:plasma (rat)RGD 
GipMouseobesity  ISOGip (Rattus norvegicus)protein:increased expression:plasma (rat)RGD 

Objects Annotated

Genes (Rattus norvegicus)
Gip  (gastric inhibitory polypeptide)

Genes (Mus musculus)
Gip  (gastric inhibitory polypeptide)

Genes (Homo sapiens)
GIP  (gastric inhibitory polypeptide)


Additional Information