[Expression of Kiss-1 mRNA in the hypothalamus of true precocious female rats].
OBJECTIVE
To investigate the gene expression of Kiss-1 in the hypothalamus of true precocious female rats at various stages of development.


METHODS
Forty 5-day-old normal female Sprague-Dawley rats were randomly assigned into four groups of 10 rats: Control group 1, Control group 2, Model group 1 and Model group 2. The rats from the two model groups were injected with 300 microg of danazol at 5 days of age to induce true precocious puberty. The two control groups were injected with normal saline instead. For the determination of Kiss-1 mRNA expression in the hypothalamus, the rats of the Model group 1 were sacrificed during the first diestrus (early puberty) and meanwhile the rats of the Control group 1 were sacrificed when they were at prepuberty; the Control group 2 rats were sacrificed at the first diestrus (early puberty); the rats of the Model group 2 were sacrificed during the second diestrus (middle puberty). The expression of Kiss-1 mRNA in the hypothalamus in the four groups was detected using semi-quantitative reverse transcription polymerase chain reaction (RT-PCR).


RESULTS
Kiss-1 mRNA expression in the hypothalamus in Model group 1 and Model group 2 increased by 1.4-fold and 2.8-fold, respectively, compared with that of Control group 1 (P < 0.05). Model group 2 showed significantly higher Kiss-1 mRNA levels than Model group 1 (P < 0.05). There were no statistical differences in the Kiss-1 mRNA expression between Control group 2 and Model group 1.


CONCLUSIONS
Gene expression of Kiss-1 is associated with the developmental period of true precocious puberty, suggesting that Kiss-1 might play a role in the pathogenesis of this disorder.
Liu
Xiao-Hui
XH
Department of Pediatrics, Tongji Hospital-Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
Liu
Fang
F
Xia
Zhi
Z
Lin
Han-Hua
HH
D000818:Animals; D005260:Female; D007031:Hypothalamus / Q000378:metabolism*; D059648:Kisspeptins; D007986:Luteinizing Hormone / Q000097:blood; D011506:Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis*; D051381:Rats; D017208:Rats, Wistar; D012741:Sexual Maturation / Q000502:physiology*
C491406:Kiss1 protein, rat; D059648:Kisspeptins; D011506:Proteins; D012333:RNA, Messenger; D007986:Luteinizing Hormone