[Effect of PP60c-Src on angiotensin II-induced signal transduction in rat vascular smooth muscle cells].
To further clarify the mechanism of Ang II-induced intracellular signal transduction in vascular smooth muscle cells(VSMCs) proliferation by observing the effect of c-Src on Ang II-mediated MAPK activation and c-fos protein expressions in rat VSMCs.



Aortic VSMCs from SD rats were cultured primarily and subcultured, which were transfected with anti-sense c-Src oligodeoxynucleotides(ODNs) wrapped with lipofectin to inhibit c-Src activity and protein production. Untransfected VSMCs were used as control, to observe the role of Ang II stimulation in MAPK activation and c-fos protein expression in VSMC. Protein immunoprecipitation and kinase phosphorylation were employed to measure c-Src kinase activity; MAPK kinase activity was assessed by the phosphorylation rate of the substrate MBP(Myelin Basic Protein); Western blot was used to assess the protein expression of c-Src and c-fos.



c-Src protein expressions in VSMC, which were transfected with different concentrations of anti-sense c-Src ODNs, were significantly decreased in a negative dose-effect manner (0.2 microm, 0.5 microm, 1.0 microm and 2.0 microm were 68.2%, 34.7%, 30.3% and 15.8% respectively compared with control). c-Src kinase activity was also obviously inhibited. Following stimulation of Ang II on VSMC transfected with anti-sense c-Src ODNs, the increase of c-Src activity was only 8.7% of control,the activity of MAPK only 1.6% compared with control, and the increase in c-fos protein expression 30.3% as control.



Ang II can induce c-Src activation and intracellular signal transduction in VSMC which depend on c-Src activation, indicating that c-Src is a pivotal signal factor in VSMC proliferation.
The Second Affiliated Hospital, College of Medical Sciences, Zhejiang University, Hangzhou 310009, China.
Mei-xiang
MX
Xiang
Dong
D
Liu
Peng
P
Chen
Jun-Sheng
JS
Lu
D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D008297:Male; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D016376:Oligonucleotides, Antisense / Q000494:pharmacology; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000032:analysis / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects*
D016376:Oligonucleotides, Antisense; D000804:Angiotensin II; D016392:Proto-Oncogene Proteins pp60(c-src); D020928:Mitogen-Activated Protein Kinases