ID 110859
Author
Tanaka, Michiko Department of Food Sciences and Nutritional Health, Kyoto Prefectural University
Kido, Yasuhiro Department of Food Sciences and Nutritional Health, Kyoto Prefectural University
Keywords
galanin
serotonin
macronutrient selection
carbohydrate-preferring
fat-preferring
fasted rats
Content Type
Journal Article
Description
We investigated macronutrient intake after intraventricular injection of galanin (GAL, 3 nmol/5 μl/rat) and/or serotonin (5-HT, 50 nmol/5μl/rat) in self-selecting fasted rats with preferences for either carbohydrates or fats. GAL injection significantly increased carbohydrate and total intake in all rats irrespective of macronutrient preference, whereas 5-HT alone did not affect macronutrient intake. The GAL-induced increase in total intake decreased to the level of saline controls when GAL was coinjected with 5- HT. The ratio of kilocalories of carbohydrates, fats and proteins (macronutrient energy ratio) after injections of GAL and/or 5-HT was similar to the saline control. In carbohydrate- preferring rats, GAL increased carbohydrate, protein and fat intake as well as total intake. Coinjection of GAL and 5-HT tended to decrease carbohydrate intake, but increase protein and fat intake. The macronutrient energy ratio after injection of GAL did not change, but the carbohydrate energy ratio decreased after 5-HT was injected, with or without GAL. In contrast, in fat-preferring rats, GAL significantly increased carbohydrate intake. Injection of 5-HT with or without GAL did not change total macronutrient intake. The macronutrient energy ratio did not change after GAL injection with or without 5-HT. These differences suggest that macronutrient preferences should be considered in any macronutrient intake study, and that serotonergic neurons play a part in the regulation of GAL-induced macronutrient intake.
Journal Title
The journal of medical investigation : JMI
ISSN
13431420
NCID
AA11166929
Volume
55
Issue
3-4
Start Page
196
End Page
203
Sort Key
196
Published Date
2008-08
FullText File
language
eng
TextVersion
Publisher