胃制造的一种帮助引起饥饿的激素——生长激素释放肽（Ghrelin）可能也在酒精依赖的发展中起作用。Elisabet Jerlhag及其同事发现，给小鼠服用生长激素释放肽导致了酒精摄入的增加，而阻断生长激素释放肽的作用能减少酒精摄入。
此前的研究发现了在大脑的对于承认奖赏起到重要作用的特定区域中存在生长激素释放肽的受体。由于这些机制看上去调控着食物和酒精的奖赏，这组作者提出了一个假说，即生长激素释放肽可能也调控着酒精依赖。直接向小鼠大脑的奖赏节点提供生长激素释放肽能让它们比接受了生理盐水的小鼠多摄入大约45%的酒精。当作者给小鼠服用干扰生长激素释放肽信号传导的两种化合物中的任意一种的时候，酒精摄入也下降了。
这组作者说，拥有较低生长激素释放肽信号传导的小鼠似乎与对酒精的奖赏特性的反应更低，这是因为它们的大脑产生了较少的多巴胺。这组作者得出结论说，这些酒精奖赏效应构成了成瘾过程的密不可分的一部分，而生长激素释放肽系统提供了治疗的一个新目标。（生物谷Bioon.com）
生物谷推荐原始出处：
PNAS June 29, 2009, doi: 10.1073/pnas.0812809106
Requirement of central ghrelin signaling for alcohol reward
Elisabet Jerlhaga,1, Emil Egecioglub, Sara Landgrena, Nicolas Saloméb, Markus Heiligc, Diederik Moecharsd, Rakesh Dattae, Daniel Perrissoudf, Suzanne L. Dicksonb,2 and J?rgen A. Engel
The stomach-derived hormone ghrelin interacts with key CNS circuits regulating energy balance and body weight. Here we provide evidence that the central ghrelin signaling system is required for alcohol reward. Central ghrelin administration (to brain ventricles or to tegmental areas involved in reward) increased alcohol intake in a 2-bottle (alcohol/water) free choice limited access paradigm in mice. By contrast, central or peripheral administration of ghrelin receptor (GHS-R1A) antagonists suppressed alcohol intake in this model. Alcohol-induced locomotor stimulation, accumbal dopamine release and conditioned place preference were abolished in models of suppressed central ghrelin signaling: GHS-R1A knockout mice and mice treated with 2 different GHS-R1A antagonists. Thus, central ghrelin signaling, via GHS-R1A, not only stimulates the reward system, but is also required for stimulation of that system by alcohol. Our data suggest that central ghrelin signaling constitutes a potential target for treatment of alcohol-related disorders.
