Orexin reverses cholecystokinin-induced reduction in feeding

Diabetes Obes Metab. 2002 Nov;4(6):399-401. doi: 10.1046/j.1463-1326.2002.00234.x.


Aim: This study was designed to investigate the effect of orexin on anorexia induced by cholecystokinin (CCK),a peripheral satiety signal.

Methods: We administered orexin A (0.01-1 nmol/mouse) and CCK-8 (3 nmol/mouse) to mice. Food intake was measured at different time-points: 20 min, 1, 2 and 4 h post-intracerebroventricular (i.c.v.) or intraperitoneal (i.p.) administrations.

Results: Intracerebroventricular-administered orexin significantly increased food intake in a dose-dependent manner. The inhibitory effect of i.p.-administered CCK-8 on food intake was significantly negated by the simultaneous i.c.v. injection of orexin in a dose-dependent manner.

Conclusions: Orexin reversed the CCK-induced loss of appetite. Our results indicate that orexin might be a promising target for pharmacological intervention in the treatment of anorexia and cachexia induced by various diseases.

MeSH terms

  • Analysis of Variance
  • Animals
  • Anorexia / chemically induced*
  • Carrier Proteins / administration & dosage
  • Carrier Proteins / pharmacology*
  • Cholecystokinin / adverse effects*
  • Dose-Response Relationship, Drug
  • Eating / drug effects*
  • Intracellular Signaling Peptides and Proteins*
  • Mice
  • Neuropeptides / administration & dosage
  • Neuropeptides / pharmacology*
  • Orexins
  • Weight Loss


  • Carrier Proteins
  • Intracellular Signaling Peptides and Proteins
  • Neuropeptides
  • Orexins
  • Cholecystokinin