Effect of losartan and captopril on expression of cardiac angiotensin II AT1 receptor mRNA in rats following myocardial infarction.
OBJECTIVE
To study the effects of losartan (Los) and captopril (Cap) treatment on expression of cardiac angiotensin II (Ang) AT1 receptor mRNA in rats following myocardial infarction (MI).


METHODS
Twenty-four rats with MI after coronary ligation for 7 d were randomly divided into 4 groups: A) Cap in drinking water, ad lib (2 g.L-1), B) i.g. Los 10 mg.kg-1.d-1, C) i.g. Los 30 mg.kg-1.d-1, and D) placebo for 6 wk. Sham-ligation rats (group E) served as controls. The levels of cardiac Ang AT1 receptor mRNA expression in each group (n = 6) were examined by Dot blot using digoxigenin-labeled cDNA probes.


RESULTS
Comparing with reflected peak areas of hybridization positive signals in group D (2640 +/- 201 micron 2), the expression of the cardiac Ang AT1 receptor mRNA was much lower in the 3 treated groups (group A 1360 +/- 134 micron 2, group B 1430 +/- 244 micron 2, group C 1310 +/- 95 micron 2) (P < 0.01). But no difference was found between the 3 treated groups and sham-ligation group (1230 +/- 233 micron 2) (P > 0.05).


CONCLUSIONS
Los and Cap attenuated the increase of cardiac Ang AT1 receptor mRNA expression in rats following MI.
D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology; D000818:Animals; D002216:Captopril / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects; D019808:Losartan / Q000494:pharmacology*; D008297:Male; D009203:Myocardial Infarction / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D044140:Receptor, Angiotensin, Type 1; D011945:Receptors, Angiotensin / Q000096:biosynthesis* / Q000235:genetics