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Identification of Orexin and Endocannabinoid Receptors in Adult Zebrafish Using Immunoperoxidase and Immunofluorescence Methods
Published on: June 25, 2019
Central orexin-A increases colonic motility in conscious rats
Tsukasa Nozu1, Shima Kumei, Kaoru Takakusaki
1Department of Regional Medicine and Education, Asahikawa Medical University, Midorigaoka Higashi 2-1-1-1, Asahikawa, Japan. tnozu@sea.plala.or.jp
Neuroscience Letters
|May 18, 2011
Summary
Brain orexin-A stimulates colonic motility and increases fecal output in rats. This study reveals orexin-A
Area of Science:
- Neurogastroenterology
- Gastrointestinal Physiology
Background:
- Brain orexin is known to regulate upper gastrointestinal functions.
- The role of brain orexin in lower gastrointestinal tract physiology remains largely unknown.
Purpose of the Study:
- To investigate the involvement of central orexin-A in the regulation of colonic motility.
Main Methods:
- Rats were administered intracisternal or intraperitoneal injections of orexin-A.
- Fecal pellet output and colonic pressure waves were measured in conscious, freely moving rats.
Main Results:
- Intracisternal orexin-A dose-dependently increased fecal pellet output.
- Central orexin-A administration significantly enhanced colonic motor contractions.
Conclusions:
- Orexin-A acts centrally to stimulate colonic motility and enhance fecal pellet output in rats.
- Brain orexin-A may mediate cephalic phase gut stimulation, including colonic motility.
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