Abstract | RATIONALE: Stress-induced inhibition of food intake is reportedly blocked by a selective corticotropin-releasing factor (CRF) type 1 receptor (CRF1) antagonist, suggesting the involvement of CRF1 in the inhibitory mechanism. CRF1 and CRF2 are considered to function in the inhibition of food intake by CRF-related peptides with different time courses. OBJECTIVES: This study was designed to clarify whether CRF2 is also involved in stress-induced inhibition of food intake and to examine the relation of CRF1to CRF2 in the inhibitory mechanism. METHODS:
Antisauvagine-30 (AS-30), a selective CRF2 antagonist, and/or CRA1000, a selective CRF1 antagonist, were pre-administered intracerebroventricularly and intraperitoneally, respectively, to male Wistar rats deprived of food for 24 h before the animals were exposed to a 1-h period of stressors and food intake in 1 h after stress exposure was examined. The effect of both antagonists on locomotor activity was also examined. RESULTS: Pre-administration of 5-30 microg of AS-30 attenuated inhibition of food intake induced by restraint, electric footshock or emotional stress using a communication box. CRA1000 also attenuated the restraint-induced inhibition of food intake at doses of 5 and 10 mg/kg body weight. The reversal of restraint-induced inhibition of food intake by co-administration of AS-30 and CRA1000 was not larger than that by AS-30 or CRA1000 alone. Both antagonists did not affect locomotor activity. CONCLUSIONS: These results suggest that not only CRF1, but also CRF2, are involved in stress-induced inhibition of food intake, and that both subtypes of CRF receptor function probably in series in 1 h after stress exposure.
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Authors | Azusa Sekino, Hisayuki Ohata, Asuka Mano-Otagiri, Keiko Arai, Tamotsu Shibasaki |
Journal | Psychopharmacology
(Psychopharmacology (Berl))
Vol. 176
Issue 1
Pg. 30-8
(Oct 2004)
ISSN: 0033-3158 [Print] Germany |
PMID | 15071721
(Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- CRF receptor type 2
- Peptide Fragments
- Pyridines
- Pyrimidines
- Receptors, Corticotropin-Releasing Hormone
- antisauvagine 30
- CRA1000
- CRF receptor type 1
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Topics |
- Animals
- Dose-Response Relationship, Drug
- Drug Therapy, Combination
- Eating
(drug effects, physiology)
- Electroshock
(adverse effects, methods)
- Food Deprivation
(physiology)
- Injections, Intraperitoneal
- Injections, Intraventricular
- Japan
- Male
- Methods
- Motor Activity
(physiology)
- Peptide Fragments
(pharmacology)
- Pyridines
(pharmacology, therapeutic use)
- Pyrimidines
(pharmacology, therapeutic use)
- Rats
- Rats, Wistar
- Receptors, Corticotropin-Releasing Hormone
(administration & dosage, antagonists & inhibitors, physiology)
- Stress, Psychological
(physiopathology, prevention & control)
- Time Factors
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