title: High fat diet induces central obesity, insulin resistance and microvascular dysfunction in hamsters.
abstract: Microvascular dysfunction is an early finding in obesity possibly related to co-morbidities like diabetes and hypertension. Therefore we have investigated changes on microvascular function, body composition, glucose and insulin tolerance tests (GTT and ITT) on male hamsters fed either with high fat (HFD, n=20) or standard (Control, n=21) diet during 16 weeks. Total body fat and protein content were determined by carcass analysis, aorta eNOS and iNOS expression by immunoblotting assay and mean blood pressure (MAP) and heart rate (HR) by an arterial catheter. Microvascular reactivity in response to acetylcholine and sodium nitroprusside, functional capillary density (FCD), capillary recruitment induced by a hyperinsulinemic status and macromolecular permeability after 30 min ischemia was assessed on either cheek pouch or cremaster muscle preparations. Compared to Control, HFD animals have shown increased visceral fat (6.0 ± 0.8 vs. 13.8 ± 0.6g/100g BW), impaired endothelial dependent vasodilatation, decreased FCD (11.3 ± 1.3 vs. 6.8 ± 1.2/field) and capillary recruitment during hyperinsulinemia and increased macromolecular permeability after ischemia/reperfusion (86.4 ± 5.2 vs.105.2 ± 5.1 leaks/cm(2)), iNOS expression and insulin resistance. MAP, HR, endothelial independent vasodilatation and eNOS expression were not different between groups. Our results have shown that HFD elicits an increase on visceral fat deposition, microvascular dysfunction and insulin resistance in hamsters.
authors: Laboratory for Clinical and Experimental Research on Vascular Biology (BioVasc), State University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors: Rute R S
authors: RR
authors: Costa
authors: Nivaldo Ribeiro
authors: NR
authors: Villela
authors: Maria das Graças C
authors: Md
authors: Souza
authors: Beatriz C S
authors: BC
authors: Boa
authors: Fátima Z G A
authors: FZ
authors: Cyrino
authors: Simone V
authors: SV
authors: Silva
authors: Patricia C
authors: PC
authors: Lisboa
authors: Egberto G
authors: EG
authors: Moura
authors: Thereza Christina
authors: TC
authors: Barja-Fidalgo
authors: Eliete
authors: E
authors: Bouskela
mesh_terms: D050154:Adiposity; D000818:Animals; D001011:Aorta / Q000201:enzymology; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D015153:Blotting, Western; D002199:Capillary Permeability; D006224:Cricetinae; D059305:Diet, High-Fat; D004195:Disease Models, Animal; D005951:Glucose Tolerance Test; D006339:Heart Rate; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D050152:Intra-Abdominal Fat / Q000503:physiopathology; D008297:Male; D008647:Mesocricetus; D008833:Microcirculation / Q000187:drug effects; D055806:Microvessels / Q000187:drug effects / Q000503:physiopathology*; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism; D056128:Obesity, Abdominal / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology; D013997:Time Factors; D014652:Vascular Diseases / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology; D014664:Vasodilation; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D001786:Blood Glucose; D007328:Insulin; D014665:Vasodilator Agents; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III