Chronic kinin receptor blockade attenuates the antihypertensive effect of ramipril.
Hypertension
; 20(1): 74-9, 1992 Jul.
Article
em En
| MEDLINE
| ID: mdl-1319960
ABSTRACT
The contribution of endogenous kinins to the chronic antihypertensive effect of angiotensin converting enzyme inhibitors was investigated in two-kidney, one clip hypertensive Wistar rats, using the new bradykinin B2-receptor antagonist HOE 140 (D-Arg, [Hyp3, Thi5, D-Tic7, Oic8]-bradykinin). In a first protocol, rats were pretreated orally with the angiotensin converting enzyme inhibitor ramipril (1 mg/kg per day), for 4 weeks. Acute blockade of bradykinin receptors by intravenous injections of HOE 140 at doses of 8.4 and 100 micrograms/kg, which inhibited the depressor responses to exogenous bradykinin, did not affect the antihypertensive effect of ramipril in these animals. Bradykinin receptors were then blocked chronically by subcutaneous infusion of HOE 140 (500 micrograms/kg per day) via osmotic minipumps for 6 weeks, while ramipril treatment was continued. HOE 140 partially reversed the antihypertensive effect of ramipril from 115.3 +/- 4.6 to 123.8 +/- 3.3 mm Hg (mean arterial blood pressure) after 3 weeks and to 121.3 +/- 2.9 mm Hg after 6 weeks. In contrast, in controls (ramipril plus subcutaneous vehicle infusion) mean arterial blood pressure decreased further from 112.0 +/- 6.0 to 110.3 +/- 4.9 mm Hg after 3 weeks and to 103.7 +/- 5.0 mm Hg after 6 weeks (p less than 0.05 and p less than 0.01, HOE 140 versus controls). Plasma catecholamines were not significantly different between the two groups at the end of the experiment, indicating that the partial reversal of the antihypertensive effect was not due to a bradykinin-like agonistic effect on catecholamine release.(ABSTRACT TRUNCATED AT 250 WORDS)
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Compostos Bicíclicos com Pontes
/
Bradicinina
/
Receptores de Neurotransmissores
/
Hipertensão Renovascular
/
Anti-Hipertensivos
Tipo de estudo:
Guideline
Limite:
Animals
Idioma:
En
Revista:
Hypertension
Ano de publicação:
1992
Tipo de documento:
Article