Intragastric gavage with denatonium benzoate acutely induces neuronal activation in the solitary tract nucleus via the vagal afferent pathway.
10.4142/jvs.2014.15.4.459
- Author:
Hyo Young JUNG
1
;
Woosuk KIM
;
Dae Young YOO
;
Sung Min NAM
;
Jong Whi KIM
;
Jung Hoon CHOI
;
Yeo Sung YOON
;
Hye Young KIM
;
In Koo HWANG
Author Information
1. Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul 151-742, Korea. vetmed2@snu.ac.kr
- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
- Keywords:
bitter tastant;
c-Fos;
nucleus tractus solitarius;
vagal afferent fibers;
vagotomy
- MeSH:
Adjuvants, Immunologic/pharmacology;
Afferent Pathways/physiology;
Animals;
Injections/veterinary;
Ligands;
Male;
Proto-Oncogene Proteins c-fos/*metabolism;
Quaternary Ammonium Compounds/*pharmacology;
Rats;
Rats, Sprague-Dawley;
Receptors, G-Protein-Coupled/*metabolism;
Solitary Nucleus/*physiology;
Vagus Nerve/*drug effects/*physiology
- From:Journal of Veterinary Science
2014;15(4):459-464
- CountryRepublic of Korea
- Language:English
-
Abstract:
Natural toxic substances have a bitter taste and their ingestion sends signals to the brain leading to aversive oral sensations. In the present study, we investigated chronological changes in c-Fos immunoreactivity in the nucleus tractus solitarius (NTS) to study the bitter taste reaction time of neurons in the NTS. Equal volumes (0.5 mL) of denatonium benzoate (DB), a bitter tastant, or its vehicle (distilled water) were administered to rats intragastrically. The rats were sacrificed at 0, 0.5, 1, 2, 4, 8, or 16 h after treatment. In the vehicle-treated group, the number of c-Fos-positive nuclei started to increase 0.5 h after treatment and peaked 2 h after gavage. In contrast, the number of c-Fos-positive nuclei in the DB-treated group significantly increased 1 h after gavage. Thereafter, the number of c-Fos immunoreactive nuclei decreased over time. The number of c-Fos immunoreactive nuclei in the NTS was also increased in a dose-dependent manner 1 h after gavage. Subdiaphragmatic vagotomy significantly decreased DB-induced neuronal activation in the NTS. These results suggest that intragastric DB increases neuronal c-Fos expression in the NTS 1 h after gavage and this effect is mediated by vagal afferent fibers.
