Effects of angiotensin II on connexin 43 of VSMCs in arteriosclerosis.
OBJECTIVE
To observe the effect of angiotensin II (Ang II) on expression of gap junction channel protein connexin 43 (Cx43) in the proliferation process of vascular smooth muscle cells (VSMCs) during the early stage of arteriosclerosis.


METHODS
Thirty-two adult male rabbits were randomly divided into 4 groups. Rabbits in Group A were fed common diet while others in Groups B, C, and D were fed high-cholesterol diet. Losartan (10 mg/(kg.d)) and ramipril (0.5 mg/(kg.d)) were added in the diet of Groups C and D, respectively. The animals were sacrificed after 8 weeks and abdominal aortas were removed and dissected. The expression of Cx43 was assayed using RT-PCR and Western Blotting analysis.


RESULTS
Cx43 was increased markedly in both protein and mRNA level in Groups B, C, and D fed high-cholesterol diet compared with that in control group (P<0.01). Cx43 level in losartan or ramipril treated groups was higher than that in control group (P<0.01, P<0.05), but lower than that in high-cholesterol diet groups (P<0.05, P<0.01).


CONCLUSIONS
Cx43 level was upregulated in VSMCs during early atherosclerosis. Losartan and ramipril can inhibit the expression of Cx43.
Cai
Wei
W
Department of Internal Medicine, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, China.
Ruan
Li-ming
LM
Wang
Yi-na
YN
Chen
Jun-zhu
JZ
D000804:Angiotensin II / Q000502:physiology*; D000818:Animals; D001161:Arteriosclerosis / Q000378:metabolism*; D001835:Body Weight; D002784:Cholesterol / Q000097:blood; D018031:Connexin 43 / Q000032:analysis / Q000235:genetics*; D019808:Losartan / Q000494:pharmacology; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000378:metabolism*; D032389:Myocytes, Smooth Muscle / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D011817:Rabbits; D017257:Ramipril / Q000494:pharmacology
D018031:Connexin 43; D012333:RNA, Messenger; D000804:Angiotensin II; D002784:Cholesterol; D019808:Losartan; D017257:Ramipril