Regression of XXXX by converting enzyme inhibition in 12-15-month-old spontaneously @entity101 @entity35 : effects on coronary resistance and ventricular compliance in normoxia and @entity519 .

@entity101 @entity1184 @entity519 @entity4346 @entity35 @entity21594
The effects of @entity21594 , a converting enzyme inhibitor (CEI), on left ventricular (LV) diastolic stiffness and coronary vascular resistance (CVR), were studied with an isolated heart preparation in 15-month-old spontaneously @entity101 @entity35 (SHR). The @entity101 animals were treated for 3 months with @entity21594 (0.3 mg/kg/day) (SHRT), and compared with untreated age-matched @entity35 -Kyoto @entity35 (WKY) and SHR. @entity21594 treatment resulted in 15% diminution in blood pressure (BP). In contrast, it completely normalized left ventricular (LV) weight. Untreated SHR, as compared with WKY, had a dilated LV and increased diastolic tissue stiffness. @entity21594 had no effect on either chamber or tissue stiffness. Five-minute @entity519 resulted in the same dramatic increase in chamber stiffness in every experimental group. During @entity519 , as during normoxia, tissue stiffness was still greater in SHR than in WKY. A major effect of CEI was to normalize the tissue stiffness of SHR under @entity519 . Coronary vascular resistance (CVR) was increased in SHR as compared with WKY. @entity21594 improves CVR and significantly shifts the coronary pressure flow curve to the dilatory side. Both collagen concentration (approximately 2 mg/g) and the content in slow V3 myosin isoform, used as biologic markers of cardiac senescence, were the same in the three experimental groups, but higher than in young hearts. @entity21594 had no effect on these parameters. In semisenescent SHR, despite having rather slight effect on arterial pressure, @entity21594 completely normalized LV weight. In addition, collagen content and its physiologic counterpart, tissue stiffness, were unaffected by 3-month treatment with @entity21594 . Nevertheless, the @entity519 -induced increase in LV tissue stiffness was improved by @entity21594 in parallel with reduction in @entity4346 ( @entity1184 ).
