胃制造的一種幫助引起饑餓的激素——生長(zhǎng)激素釋放肽（Ghrelin）可能也在酒精依賴(lài)的發(fā)展中起作用,。Elisabet Jerlhag及其同事發(fā)現(xiàn),，給小鼠服用生長(zhǎng)激素釋放肽導(dǎo)致了酒精攝入的增加,，而阻斷生長(zhǎng)激素釋放肽的作用能減少酒精攝入,。
此前的研究發(fā)現(xiàn)了在大腦的對(duì)于承認(rèn)獎(jiǎng)賞起到重要作用的特定區(qū)域中存在生長(zhǎng)激素釋放肽的受體,。由于這些機(jī)制看上去調(diào)控著食物和酒精的獎(jiǎng)賞,，這組作者提出了一個(gè)假說(shuō),，即生長(zhǎng)激素釋放肽可能也調(diào)控著酒精依賴(lài),。直接向小鼠大腦的獎(jiǎng)賞節(jié)點(diǎn)提供生長(zhǎng)激素釋放肽能讓它們比接受了生理鹽水的小鼠多攝入大約45%的酒精。當(dāng)作者給小鼠服用干擾生長(zhǎng)激素釋放肽信號(hào)傳導(dǎo)的兩種化合物中的任意一種的時(shí)候,，酒精攝入也下降了,。
這組作者說(shuō)，擁有較低生長(zhǎng)激素釋放肽信號(hào)傳導(dǎo)的小鼠似乎與對(duì)酒精的獎(jiǎng)賞特性的反應(yīng)更低,，這是因?yàn)樗鼈兊拇竽X產(chǎn)生了較少的多巴胺,。這組作者得出結(jié)論說(shuō)，這些酒精獎(jiǎng)賞效應(yīng)構(gòu)成了成癮過(guò)程的密不可分的一部分,，而生長(zhǎng)激素釋放肽系統(tǒng)提供了治療的一個(gè)新目標(biāo),。（生物谷Bioon.com）
生物谷推薦原始出處：
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.
