Abstract |
This study was designed to investigate the effects of antihypertensive drugs on vascular hypertrophy and vascular angiotensin II in vivo in spontaneously hypertensive rats (SHR). Hydralazine (10 mg/kg/day), delapril ( angiotensin converting enzyme inhibitor; 20 mg/kg/day), manidipine ( calcium channel blocker; 10 mg/kg/day), and vehicle were given by gavage to four groups of SHR between 4 and 5 months of age. The aortic angiotensin II level was measured by highly sensitive radioimmunoassay coupled with high pressure liquid chromatography; aortic morphologic studies were performed. Each drug treatment effectively lowered blood pressure to the same level. However, the aortic wall thickness, medial-intimal areas, and wall to lumen ratio of abdominal aorta decreased significantly (p < 0.05, p < 0.01, p < 0.01, respectively) with delapril and manidipine but not hydralazine. Delapril significantly decreased aortic angiotensin II levels (p < 0.05), whereas manidipine treatment significantly increased them (p < 0.05). The aortic angiotensin II level was not changed by hydralazine. These results show that delapril and manidipine caused regression of hypertension-induced vascular hypertrophy in SHR. The probable mechanism of regression of aortic hypertrophy by delapril was inhibition of vascular angiotensin II formation, but the mechanism for manidipine was unclear.
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Authors | R Morishita, J Higaki, F Nakamura, N Tomita, H Yu, M Nagano, H Mikami, T Ogihara |
Journal | Blood pressure. Supplement
(Blood Press Suppl)
Vol. 3
Pg. 41-7
( 1992)
ISSN: 0803-8023 [Print] Sweden |
PMID | 1343288
(Publication Type: Journal Article)
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Chemical References |
- Angiotensin-Converting Enzyme Inhibitors
- Antihypertensive Agents
- Calcium Channel Blockers
- Dihydropyridines
- Indans
- Nitrobenzenes
- Piperazines
- Angiotensin II
- Hydralazine
- manidipine
- delapril
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Topics |
- Angiotensin II
(metabolism)
- Angiotensin-Converting Enzyme Inhibitors
(pharmacology)
- Animals
- Antihypertensive Agents
(pharmacology)
- Aorta, Abdominal
(drug effects, pathology, physiology)
- Blood Pressure
(drug effects)
- Calcium Channel Blockers
(pharmacology)
- Dihydropyridines
(pharmacology)
- Hydralazine
(pharmacology)
- Hypertension
(complications, drug therapy)
- Hypertrophy
(drug therapy, etiology)
- Indans
(pharmacology)
- Male
- Nitrobenzenes
- Piperazines
- Rats
- Rats, Inbred SHR
- Renin-Angiotensin System
(drug effects, physiology)
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