The gastroduodenal branch of the common hepatic vagus regulates voluntary lard intake, fat deposition, and plasma metabolites in streptozotocin-diabetic rats.
The common hepatic branch of the vagus nerve negatively regulates lard intake in rats with streptozotocin (STZ)-induced, insulin-dependent diabetes. However, this branch consists of two subbranches: the hepatic branch proper, which serves the liver, and the gastroduodenal branch, which serves the distal stomach, pancreas, and duodenum. The aim of this study was to determine whether the gastroduodenal branch specifically regulates voluntary lard intake. We performed a gastroduodenal branch vagotomy (GV) on nondiabetic, STZ-diabetic, and STZ-diabetic insulin-treated groups of rats and compared them with sham-operated counterparts. All rats had high steady-state corticosterone levels to maximize lard intake. Five days after surgery, all rats were provided with the choice of chow or lard to eat for another 5 days. STZ-diabetes resulted in a reduction in lard intake that was partially rescued by either GV or insulin treatment. Patterns of white adipose tissue (WAT) deposition differed after GV- and insulin-induced lard intake, with subcutaneous WAT increasing exclusively after the former and mesenteric WAT increasing exclusively in the latter. GV also prevented the insulin-induced reduction in the STZ-elevated plasma glucagon, triglycerides, free fatty acids, and total ketone bodies but did not alter the effect of insulin-induced reduction of plasma glucose levels. These data suggest that the gastroduodenal branch of the vagus inhibits lard intake and regulates WAT deposition and plasma metabolite levels in STZ-diabetic rats.
Warne
James P
JP
Dept. of Physiology, Box 0444, Univ. of California San Francisco, 513 Parnassus Ave., San Francisco, CA 94143, USA. james.warne@ucsf.edu
Foster
Michelle T
MT
Horneman
Hart F
HF
Pecoraro
Norman C
NC
de Jong
Hanna K
HK
Ginsberg
Abigail B
AB
Akana
Susan F
SF
Dallman
Mary F
MF
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D050218:Body Fat Distribution; D003345:Corticosterone / Q000097:blood; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy / Q000378:metabolism*; D004041:Dietary Fats / Q000494:pharmacology; D004435:Eating / Q000502:physiology; D005227:Fatty Acids / Q000097:blood; D005749:Gastric Inhibitory Polypeptide / Q000097:blood; D005934:Glucagon / Q000097:blood; D006003:Glycogen / Q000378:metabolism; D007004:Hypoglycemic Agents / Q000097:blood / Q000494:pharmacology; D007328:Insulin / Q000097:blood / Q000494:pharmacology; D008099:Liver / Q000294:innervation* / Q000378:metabolism*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D014628:Vagotomy; D014630:Vagus Nerve / Q000033:anatomy & histology / Q000502:physiology*; D015431:Weight Loss / Q000502:physiology
D001786:Blood Glucose; D004041:Dietary Fats; D005227:Fatty Acids; D007004:Hypoglycemic Agents; D007328:Insulin; D005749:Gastric Inhibitory Polypeptide; D006003:Glycogen; D005934:Glucagon; C029310:lard; D003345:Corticosterone