Control of feeding behavior by CRH 2 receptors in the paraventricular nucleus of the hypothalamus of adrenalectomized rats

Abstract

The Corticotropin releasing hormone (CRH), play an important role in the normal maintenance of food intake, body weight and energy metabolism. CRH is a powerful inhibitor of feeding. Urocortin 2 (Ucn 2) a CRH like peptide mediate this effect through CRH 2 receptors expressed in the paraventricular nucleus of the hypothalamus (PVN), but it is not yet know the behavior mechanism and effect on glucose and triglycerides, that acts in the presence of agonist Ucn 2 and antagonist Antisauvagine 30 (Asv 30). The aim of the present study was determinate the role of CRH 2 receptors in food intake feeding behavior and in concentration of glucose and triglycerides of adrenalectomized Wistar rats. 34 male rats of Wistar strain of 250–300 g were accustomed to a diet of separate sources of protein, carbohydrate and fat, then were implanted a cannula on right PVN and a second surgery to remove the adrenal glands bilaterally (ADX) or sham surgery (sham). After the post‐surgery recovery period of 5 days, the rats were assigned to a group and a treatment, sham (vh+vh), ADX (vh+vh), ADX Agonist (vh+Ucn 2), ADX antagonist (Asv 30+vh) and ADX pretreatment (Asv 30+Ucn 2). A record of continuous duration of 60 min was made for the analysis of the behavioral satiety sequence (BSS). The results showed that administration of Ucn 2 reduced carbohydrates intake and promotes the transition of feeding and resting in the BSS, The pretreatment with Asv‐30 delayed the transition of feeding and resting. The glucose and triglycerides concentration decrease with the administration of Ucn‐2 and the antagonist reverse this effect. In conclusion the results of this study suggest that CRH 2 receptors of the PVN are important for the regulation of feeding, glucose and triglycerides in adrenalectomized rats.Research support: DGAPA IN306711