Hepatic Branch Vagotomy, Like Insulin Replacement, Promotes Voluntary Lard Intake in Streptozotocin-Diabetic Rats

• Published in: Endocrinology (Philadelphia) 2007-07, Vol.148 (7), p.3288-3298
• Main Authors: Warne, James P, Foster, Michelle T, Horneman, Hart F, Pecoraro, Norman C, Ginsberg, Abigail B, Akana, Susan F, Dallman, Mary F
• Format: Article
• Language: English
• Subjects: Ablation; Adipose tissue; Adipose Tissue, White - drug effects; Adipose Tissue, White - metabolism; Animals; Biological and medical sciences; Blood Glucose - metabolism; Body fat; Body Weight - drug effects; Corticosterone; Corticosterone - administration & dosage; Corticosterone - pharmacology; Diabetes; Diabetes mellitus; Diabetes Mellitus, Experimental - chemically induced; Diabetes Mellitus, Experimental - physiopathology; Diabetes Mellitus, Experimental - therapy; Diabetes. Impaired glucose tolerance; Dietary Fats - administration & dosage; Dietary Fats - metabolism; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Energy Intake - drug effects; Etiopathogenesis. Screening. Investigations. Target tissue resistance; Fatty Acids, Nonesterified - blood; Food intake; Fundamental and applied biological sciences. Psychology; Glucose; Glycogen - metabolism; Homeostasis; Hypoglycemic Agents - pharmacology; Insulin; Insulin - blood; Insulin - pharmacology; Jugular vein; Ketone Bodies - blood; Liver; Male; Medical sciences; Rats; Rats, Sprague-Dawley; Streptozocin; Time Factors; Triglycerides - blood; Vagotomy; Vagotomy - methods; Vagus Nerve - physiopathology; Vertebrates: endocrinology; Weight loss
• ISSN: 0013-7227; 1945-7170
• DOI: 10.1210/en.2007-0003

Although high insulin concentrations reduce food intake, low insulin concentrations promote lard intake over chow, possibly via an insulin-derived, liver-mediated signal. To investigate the role of the hepatic vagus in voluntary lard intake, streptozotocin-diabetic rats with insulin or vehicle replaced into either the superior mesenteric or jugular veins received a hepatic branch vagotomy (HV) or a sham operation. All rats received a pellet of corticosterone that clamped the circulating steroid at moderately high concentrations to enhance lard intake. After 5 d of recovery, rats were offered the choice of lard and chow for 5 d. In streptozotocin-diabetic rats, HV, like insulin replacement, restored lard intake to nondiabetic levels. Consequently, this reduced chow intake without affecting total caloric intake, and insulin site-specifically increased white adipose tissue weight. HV also ablated the effects of insulin on reducing circulating glucose levels and attenuated the streptozotocin-induced weight loss in most groups. Collectively, these data suggest that the hepatic vagus normally inhibits lard intake and can influence glucose homeostasis and the pattern of white adipose tissue deposition. These actions may be modulated by insulin acting both centrally and peripherally.