Changes of mRNA expression of enkephalin and prodynorphin in hippocampus of rats with chronic immobilization stress.
OBJECTIVE
To observe the changes of enkephalin mRNA and prodynorphin mRNA in hippocampus of rats induced by chronic immobilization stress.


METHODS
Thirty rats were randomly divided into three groups of 10 each: the normal control group (group A), the group induced by chronic immobilization stress for 7 d (group B) and the group induced by chronic immobilization stress for 21 d (group C). The changes of the enkephalin mRNA and prodynorphin mRNA in the rat hippocampus were detected by reverse transcription-polymerase chain reaction (RT-PCR).


RESULTS
Expression levels of enkephalin mRNA and prodynorphin mRNA in rat hippocampus were significantly increased under chronic immobilization stress, and the expression of prodynorphin mRNA in the rat hippocampus in group C was remarkably higher than that in group B (0.624 +/- 0.026; n = 5; P<0.01).


CONCLUSIONS
The increased enkephalin mRNA and prodynorphin mRNA gene expressions in rat hippocampus were involved in chronic stress.
School of Basic Medical Science, Beijing University of Traditional Chinese Medicine, Beijing 100029, China. chenjiaxu@hotmail.com
Jia-Xu
JX
Chen
Wei
W
Li
Xin
X
Zhao
Jian-Xin
JX
Yang
Hong-Yan
HY
Xu
Zhu-Feng
ZF
Wang
Guang-Xin
GX
Yue
D000818:Animals; D002908:Chronic Disease; D004745:Enkephalins / Q000235:genetics*; D015870:Gene Expression; D006624:Hippocampus / Q000502:physiology*; D008297:Male; D011498:Protein Precursors / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012149:Restraint, Physical; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013312:Stress, Physiological / Q000503:physiopathology*
D004745:Enkephalins; D011498:Protein Precursors; D012333:RNA, Messenger; C033660:preproenkephalin