The antagonism of ghrelin alters the appetitive response to learned cues associated with food
The antagonism of ghrelin alters the appetitive response to learned cues associated with food
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DOI：
10.1016/j.bbr.2016.01.040
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发表时间：
2016-04-15
影响因子：
2.7
通讯作者：
Johnson, Alexander W.
中科院分区：
文献类型：
--
作者：
Dailey, Megan J.;Moran, Timothy H.;Johnson, Alexander W.
肥胖症的快速增加可能部分是由于暴露于食物线索的增加。食物配对线索在饱腹感条件下的食物采购和摄入中发挥作用。发生这种情况的机制需要表征，但可能涉及生长激素释放肽。这种促食欲肽改变了对食物配对条件刺激的反应，以及对奖赏核中食物图像的神经反应。因此，我们测试了生长激素释放肽受体拮抗剂是否改变的影响，食物配对的线索上的表现工具的反应，赚取食物和消费的食物本身使用测试的巴甫洛夫仪器转移（PIT）和线索强化喂养（CPF），分别。食物剥夺大鼠接受巴甫洛夫条件反射，其中听觉提示与蔗糖溶液的递送配对，然后通过仪器条件反射来杠杆按压蔗糖。训练后，大鼠自由进食。在测试当天，向大鼠注射生长激素释放肽受体拮抗剂GHRP-6 [D-Lys 3]，然后测试PIT或CPF。中断ghrelin信号增强PIT的表达。此外，GHRP-6 [D-Lys 3]损害了CPF中摄食行为的启动，而不影响蔗糖的总摄入量。最后，在PIT测试的大鼠，增强FOS免疫反应性被揭示以下的拮抗剂被认为是潜在的PIT的区域，然而，拮抗剂对CPF测试的大鼠FOS免疫反应性没有影响。(C)2016由Elsevier B. V.出版
The rapid increase in obesity may be partly mediated by an increase in the exposure to cues for food. Food-paired cues play a role in food procurement and intake under conditions of satiety. The mechanism by which this occurs requires characterization, but may involve ghrelin. This orexigenic peptide alters the response to food-paired conditioned stimuli, and neural responses to food images in reward nuclei. Therefore, we tested whether a ghrelin receptor antagonist alters the influence of food-paired cues on the performance of instrumental responses that earn food and the consumption of food itself using tests of Pavlovian-to-instrumental transfer (PIT) and cue potentiated feeding (CPF), respectively. Food-deprived rats received Pavlovian conditioning where an auditory cue was paired with delivery of sucrose solution followed by instrumental conditioning to lever press for sucrose. Following training, rats were given ad libitum access to chow. On test day, rats were injected with the ghrelin receptor antagonist GHRP-6 [D-Lys3] and then tested for PIT or CPF. Disrupting ghrelin signaling enhanced expression of PIT. In addition, GHRP-6 [D-Lys3] impaired the initiation of feeding behavior in CPF without influencing overall intake of sucrose. Finally, in PIT tested rats, enhanced FOS immunoreactivity was revealed following the antagonist in regions thought to underlie PIT; however, the antagonist had no effect on FOS immunoreactivity in CPF tested rats. (C) 2016 Published by Elsevier B.V.