Cosme Caitlin V, Gutman Andrea L, LaLumiere Ryan T
Department of Psychology, University of Iowa, Iowa City, IA, USA.
1] Department of Psychology, University of Iowa, Iowa City, IA, USA [2] Interdisciplinary Graduate Program in Neuroscience, University of Iowa, Iowa City, IA, USA.
Neuropsychopharmacology. 2015 Sep;40(10):2425-33. doi: 10.1038/npp.2015.92. Epub 2015 Apr 3.
Prior studies suggest that the insular cortex (IC), and particularly its posterior region (the PIc), is involved in nicotine craving and relapse in humans and rodents. The present experiments were conducted to determine whether the IC and its different subregions regulate relapse to cocaine-seeking behavior in rats. To address this issue, male Sprague-Dawley rats underwent cocaine self-administration followed by extinction training and reinstatement tests. Before each reinstatement, the PIc or the more anterior dorsal agranular IC (AId) was inactivated to determine their roles in the reinstatement to cocaine seeking. In contrast to the nicotine findings, PIc inactivation had no effect on cue-induced reinstatement for cocaine seeking. However, AId inactivation reduced cued reinstatement while having no effect on cocaine-prime reinstatement. AId inactivation had no effect on reinstatement of food-seeking behavior induced by cues, a food-prime, or cues+food-prime. Based on previous work hypothesizing a role for corticotropin-releasing factor (CRF) in the IC during craving and relapse, a subsequent experiment found that CRF receptor-1 (CRF1) blockade in the AId similarly reduced cued reinstatement. Our results suggest that the AId, along with CRF1 receptors in this region, regulates reinstatement to cocaine seeking, but not food seeking, depending on the type of reinstatement, whereas PIc activity does not influence cue-induced reinstatement.
先前的研究表明，岛叶皮质（IC），尤其是其后部区域（PIc），与人类和啮齿动物对尼古丁的渴望及复吸有关。进行本实验是为了确定IC及其不同亚区域是否调节大鼠对可卡因觅求行为的复吸。为解决这个问题，雄性Sprague-Dawley大鼠接受可卡因自我给药，随后进行消退训练和复吸测试。在每次复吸前，使PIc或更靠前的背侧无颗粒岛叶皮质（AId）失活，以确定它们在可卡因觅求复吸中的作用。与尼古丁研究结果不同，PIc失活对线索诱导的可卡因觅求复吸没有影响。然而，AId失活减少了线索诱导的复吸，同时对可卡因引发的复吸没有影响。AId失活对线索、食物引发或线索 + 食物引发所诱导的食物觅求行为的复吸没有影响。基于先前假设促肾上腺皮质激素释放因子（CRF）在渴望和复吸期间在IC中起作用的研究工作，随后的一项实验发现，AId中CRF受体-1（CRF1）的阻断同样减少了线索诱导的复吸。我们的结果表明，AId及其该区域的CRF1受体，根据复吸类型调节对可卡因觅求的复吸，但不调节对食物觅求的复吸，而PIc的活动不影响线索诱导的复吸。
