Elevated mu-opioid receptor expression in the nucleus of the solitary tract accompanies attenuated withdrawal signs after chronic low dose naltrexone in opiate-dependent rats.
Elevated mu-opioid receptor expression in the nucleus of the solitary tract accompanies attenuated withdrawal signs after chronic low dose naltrexone in opiate-dependent rats.
复制标题
在阿片依赖大鼠中，长期使用低剂量纳曲酮后，孤束核中μ阿片受体表达升高，伴随戒断症状减弱。
DOI：
10.1002/jnr.20738
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发表时间：
2006
期刊：
影响因子：
--
通讯作者：
Qian,Y
中科院分区：
文献类型：
--
作者：
VanBockstaele,EJ;Rudoy,C;Mannelli,P;Oropeza,V;Qian,Y
We previously described a decrease in withdrawal behaviors in opiate‐dependent rats that were chronically treated with very low doses of naltrexone in their drinking water. Attenuated expression of withdrawal behaviors correlated with decreased c‐Fos expression and intracellular signal transduction elements [protein kinase A regulatory subunit II (PKA) and phosphorylated cAMP response element binding protein (pCREB)] in brainstem noradrenergic nuclei. In this study, to determine whether similar cellular changes occurred in forebrain nuclei associated with drug reward, expressions of PKA and pCREB were analyzed in the ventral tegmental area, frontal cortex, striatum, and amygdala of opiate‐treated rats that received low doses of naltrexone in their drinking water. No significant difference in PKA or pCREB was detected in these regions following drug treatment. To examine further the cellular mechanisms in noradrenergic nuclei that could underlie attenuated withdrawal behaviors following low dose naltrexone administration, the nucleus of the solitary tract (NTS) and locus coeruleus (LC) were examined for opioid receptor (OR) protein expression. Results showed a significant increase in μOR expression in the NTS of morphine‐dependent rats that received low doses of naltrexone in their drinking water, and increases in μOR expression were also found to be dose dependent. Protein expression of μOR in the LC and δOR in either brain region remained unchanged. In conclusion, our previously reported decreases in c‐Fos and PKA expression in the NTS following pretreatment with low doses of naltrexone may be partially explained by a greater inhibition of NTS neurons resulting from increased μOR expression in this region. © 2005 Wiley‐Liss, Inc.
