[Changes of c-fos, c-jun mRNA expressions in cardiomyocyte hypertrophy induced by angiotensin II and effects of tanshinone II A].
OBJECTIVE
To investigate the changes of proto-oncogene c-fos, c-jun mRNA expression in angiotensin II (Ang II)-induced hypertrophy and effects of tanshinone II A (Tan) in the primary culture of neonatal rat cardiomyocytes.


METHODS
Twelve neonatal Wistar rats aged one day old of clean grade and both sexes were selected to isolate and culture cardiomyocytes. The cardiomyocytes were divided into: normal control group, Ang II (10(-6) mol x L(-1)) group, Ang II (10(-6) mol x L(-1)) +Tan (10(-8) g x L(-1)) group, Ang II (10(-6) mol x L(-1)) + valsartan (10(-6) mol x L(-1)) group, Tan (10(-8) g x L(-1)) group, valsartan (10(-6) mol x L(-1)) group. The cardiomyocyte size was determined by phase contrast microscope, the rate of protein synthesis in cardiomyocytes was measured by 3H-leucine incorporation. The c-fos, c-jun mRNA expression of cardiomyocytes were assessed using reverse transcription polymerase chain reaction (RT-PCR).


RESULTS
Ang II was added to the culture medium and 30 min later, the c-fos, c-jun mRNA expression of cardiomyocytes increased significantly (P < 0. 01). After Ang II took effect for 24 h, the rate of protein synthesis in Ang II group increased more prominently than that in normal control group (P < 0.01). After Ang II took effect for 7 days, the size of cardiomyocyte in Ang II group increased obviously (P < 0. 05). If tanshinone II or valsartan was added to the culture medium before Ang II, both of them could inhibit the increase of c-fos, c-jun mRNA expression (P < 0.01), cardiomyocyte protein synthesis rate (P < 0.01), and cardiomyocyte size (P < 0.05) induced by Ang II.


CONCLUSIONS
Tanshinone II could ameliorate Ang II-induced cardiomyocytes hypertrophy by inhabiting c-fos, c-jun mRNA expression.
Zhou
Dai-Xing
DX
Department of Emergency Medicine, Tongji Hospital of Huazhong University of Science and Technology, Wuhan 430030, China. zdx9599@sina.com
Liang
Qian-Sheng
QS
He
Xue-Xin
XX
Zhan
Cheng-Ye
CY
D045784:Abietanes; D000804:Angiotensin II / Q000096:biosynthesis / Q000494:pharmacology*; D000818:Animals; D006332:Cardiomegaly / Q000139:chemically induced* / Q000378:metabolism / Q000473:pathology; D005786:Gene Expression Regulation / Q000187:drug effects*; D016762:Genes, fos / Q000235:genetics; D016758:Genes, jun / Q000235:genetics; D032383:Myocytes, Cardiac / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D010616:Phenanthrenes / Q000494:pharmacology*; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics*; D016755:Proto-Oncogene Proteins c-jun / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013777:Tetrazoles / Q000494:pharmacology; D014633:Valine / Q000031:analogs & derivatives / Q000494:pharmacology; D000068756:Valsartan
D045784:Abietanes; D010616:Phenanthrenes; D016760:Proto-Oncogene Proteins c-fos; D016755:Proto-Oncogene Proteins c-jun; D012333:RNA, Messenger; D013777:Tetrazoles; C021751:tanshinone; D000804:Angiotensin II; D000068756:Valsartan; D014633:Valine