A comparison of the effect of angiotensin converting enzyme inhibition and angiotensin II receptor antagonism on the structural changes associated with hypertension in rat small arteries.
OBJECTIVE
To investigate whether, when angiotensin converting enzyme inhibitors are administered to young, genetically hypertension-prone animals, the demonstrated attenuation of blood pressure development and prevention of the structural changes usually observed in small arteries is attributable to the prevention of angiotensin II production.


METHODS
We have treated spontaneously hypertensive rats (SHR) aged 4-20 weeks with either lisinopril (1 or 10 mg/kg) or the angiotensin II receptor antagonist D 8731 (1, 20 or 50 mg/kg).


METHODS
Blood pressure was measured and structural parameters in small arteries from four vascular beds were examined using isometric myography.


RESULTS
At age 20 weeks lisinopril had attenuated blood pressure development and prevented cardiac hypertrophy (but not vascular hypertrophy) in a dose-dependent manner. The highest dose of lisinopril had reduced the blood pressure of the SHR to below that of the Wistar-Kyoto (WKY) rats and prevented most structural changes, but there was a slight reduction in body weight in those rats. Comparable blood pressure control with D 8731 was associated with similar structural parameters.


CONCLUSIONS
The prevention of hypertension-associated vascular structural alteration appears to be dependent upon the degree of blood pressure control.
Shaw
L M
LM
Department of Medicine, Manchester Royal Infirmary, UK.
George
P R
PR
Oldham
A A
AA
Heagerty
A M
AM
D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D000818:Animals; D001158:Arteries / Q000187:drug effects* / Q000473:pathology / Q000503:physiopathology; D001713:Biphenyl Compounds / Q000627:therapeutic use*; D006973:Hypertension / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D017379:Hypertrophy, Left Ventricular / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D017706:Lisinopril / Q000627:therapeutic use*; D008297:Male; D009929:Organ Size; D011804:Quinolines / Q000627:therapeutic use*; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY
D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D001713:Biphenyl Compounds; D011804:Quinolines; C081112:ICI D8731; D017706:Lisinopril