title: Dietary fat ingestion activates β-endorphin neurons in the hypothalamus.
abstract: The opioid system regulates food choice, consumption, and reinforcement processes, especially for palatable meals such as fatty food. β-Endorphin is known as an endogenous opioid peptide produced in neurons of the hypothalamus. In this study, we found that Intralipid (fat emulsion) ingestion increased c-fos expression in β-endorphin neurons. However, intragastric infusion of Intralipid only slightly increased c-fos expression 2h after infusion. Further, dissection of glossopharyngeal nerve, innervating posterior tongue taste buds, partially but significantly decreased the Intralipid-induced c-fos expression. These results indicate that mainly the orosensory stimulation from fat may activate β-endorphin neurons, thereby promoting β-endorphin release.
authors.affiliation: Laboratory of Nutrition Chemistry, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan. sigenobu@kais.kyoto-u.ac.jp
authors.forename: Shigenobu
authors.initials: S
authors.lastname: Matsumura
authors.forename: Ai
authors.initials: A
authors.lastname: Eguchi
authors.forename: Yoko
authors.initials: Y
authors.lastname: Okafuji
authors.forename: Sotaro
authors.initials: S
authors.lastname: Tatsu
authors.forename: Takafumi
authors.initials: T
authors.lastname: Mizushige
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tsuzuki
authors.forename: Kazuo
authors.initials: K
authors.lastname: Inoue
authors.forename: Tohru
authors.initials: T
authors.lastname: Fushiki
mesh_terms: D000818:Animals; D004041:Dietary Fats / Q000008:administration & dosage*; D004435:Eating; D007031:Hypothalamus / Q000378:metabolism*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009474:Neurons / Q000378:metabolism*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D001615:beta-Endorphin / Q000378:metabolism*
chemical_list: D004041:Dietary Fats; D016760:Proto-Oncogene Proteins c-fos; D001615:beta-Endorphin