Influence of blood pressure on development of aortic medial smooth @entity2086 in spontaneously @entity101 XXXX .

@entity1169 @entity2086 @entity101 @entity1184 @entity2514 @entity3371 @entity1808 @entity35
The hypothesis that a primary stimulus for aortic medial @entity1184 in spontaneously @entity101 @entity35 (SHR) is increased blood pressure was tested by determining whether development of smooth muscle cell @entity1184 and hyperploidy in SHR could be dissociated from blood pressure levels in @entity35 treated with various antihypertensive drugs with different mechanisms of action. @entity35 -Kyoto @entity35 (WKY) and SHR were treated between 2 and 5 months of age with @entity3371 (375 mg/L), @entity2514 (40 mg/L), or @entity1169 (1.5 mg/L) administered in their drinking water. Smooth @entity2086 and hyperploidy were analyzed by morphometric evaluation of medial smooth muscle content, flow cytometric analysis of the frequency of polyploid smooth muscle cells, and biochemical estimates of smooth muscle cell number. All drugs significantly lowered blood pressure in SHR compared with untreated controls (order of efficacy: @entity3371 greater than @entity2514 greater than @entity1169 ). @entity3371 also was most effective at changing blood pressure in WKY, while @entity1169 and @entity2514 had similar blood pressure-lowering effects. The efficacy of drugs in preventing the development of smooth muscle cell polyploidism and medial @entity1184 in SHR was the same as their efficacy in lowering blood pressure, although @entity1169 had no effect on medial smooth @entity2086 despite lowering blood pressure by 26 mm Hg. Regression analyses showed a high degree of correlation between blood pressure and the frequency of polyploid smooth muscle cells and medial smooth muscle content. These results are consistent with the hypothesis that aortic medial @entity1184 may be, in part, a response to increased blood pressure or wall stress. However, analysis of covariance and two-stage multiple regression analyses indicated that @entity3371 had an effect over and above that predicted by its blood pressure-lowering effect. Furthermore, @entity1169 lowered blood pressure but did not affect medial @entity1184 . These results suggest that smooth @entity2086 is not simply a response to increased blood pressure, but that other factors, such as @entity1808 , may be important in modulating aortic medial @entity1184 in SHR.
