학술논문
Endogenous orexin-A in the brain mediates 2-deoxy-d-glucose-induced stimulation of gastric motility in freely moving conscious rats
Original Article-Alimentary Tract
Original Article-Alimentary Tract
Document Type
Academic Journal
Author
Source
Journal of Gastroenterology. April 2012, Vol. 47 Issue 4, p404, 8 p.
Subject
Language
English
ISSN
0944-1174
Abstract
Author(s): Tsukasa Nozu [sup.1], Yoshihiro Tuchiya [sup.2], Shima Kumei [sup.2], Kaoru Takakusaki [sup.3], Koji Ataka [sup.4], Mineko Fujimiya [sup.4], Toshikatsu Okumura [sup.2] Author Affiliations: (1) grid.252427.4, 0000000086382724, Department of Regional [...]
Background Increasing evidence has indicated that brain orexin plays a vital role in the regulation of gastrointestinal (GI) physiology such as gastric acid secretion and GI motility. The aim of this study was to elucidate the effects and mechanisms of orexin on gastric motility in non-fasted rats. Methods In this study, we recorded intraluminal gastric pressure waves in freely moving conscious rats with a manometric catheter located in the antrum. We assessed the area under the manometric trace as the motor index (MI), and compared its values for 1 h before and after drug administration. Results Intracisternal (ic) injection of orexin-A (10 [mu]g) significantly increased the MI, but intraperitoneal (ip) injection did not have any effect. Pretreatment of ip injection of atropine significantly blocked the orexin-A-induced stimulation of gastric motility. Intravenous injection of 2-deoxy-d-glucose (2-DG, 200 mg/kg), a central vagal stimulant, significantly increased the MI. The ic injection of SB-334687 (40 [mu]g), a selective orexin-A antagonist, did not modify the basal MI, but this antagonist significantly suppressed the stimulant action of 2-DG. Conclusions These results suggest that endogenous orexin-A in the brain is involved in the vagal-dependent stimulation of gastric contractions.
Background Increasing evidence has indicated that brain orexin plays a vital role in the regulation of gastrointestinal (GI) physiology such as gastric acid secretion and GI motility. The aim of this study was to elucidate the effects and mechanisms of orexin on gastric motility in non-fasted rats. Methods In this study, we recorded intraluminal gastric pressure waves in freely moving conscious rats with a manometric catheter located in the antrum. We assessed the area under the manometric trace as the motor index (MI), and compared its values for 1 h before and after drug administration. Results Intracisternal (ic) injection of orexin-A (10 [mu]g) significantly increased the MI, but intraperitoneal (ip) injection did not have any effect. Pretreatment of ip injection of atropine significantly blocked the orexin-A-induced stimulation of gastric motility. Intravenous injection of 2-deoxy-d-glucose (2-DG, 200 mg/kg), a central vagal stimulant, significantly increased the MI. The ic injection of SB-334687 (40 [mu]g), a selective orexin-A antagonist, did not modify the basal MI, but this antagonist significantly suppressed the stimulant action of 2-DG. Conclusions These results suggest that endogenous orexin-A in the brain is involved in the vagal-dependent stimulation of gastric contractions.