Inhibition of angiotensin-converting enzyme (ACE) in rat plasma and tissue was studied after administration of quinapril, a new orally active ACE inhibitor with an intermediate duration of action. Tissue and plasma ACE was assessed by a radioinhibitor-binding assay and by in vitro autoradiography using [125I]351A as the radioligand. Individual tissues in rats were differentially inhibited in time and degree. The highest ACE inhibition in plasma and in tissues occurred within the first 2 h after gavage treatment with quinapril, 0.3 mg/kg. After 24 h, ACE was still inhibited by 25% in plasma, by 30% in the aorta, by 35% in the kidneys, and by more than 40% in cardiac atria and ventricles. Plasma and kidney tissues showed increasing ACE inhibition in a dose-dependent manner after oral dosing with quinapril. In the brain, only the structures outside the blood-brain barrier were inhibited after the administration of 0.1 mg/kg of quinapril. Similarly, testicular ACE was unaffected by quinapril. These results demonstrate a prolonged effect of quinapril on tissue ACE and suggest that ACE inhibition in the heart, vasculature, and kidneys may be of particular importance in pathologic states such as hypertension or heart failure.

Inhibition of angiotensin converting enzyme (ACE) in plasma and tissue

FABRIS, BRUNO;
1990

Abstract

Inhibition of angiotensin-converting enzyme (ACE) in rat plasma and tissue was studied after administration of quinapril, a new orally active ACE inhibitor with an intermediate duration of action. Tissue and plasma ACE was assessed by a radioinhibitor-binding assay and by in vitro autoradiography using [125I]351A as the radioligand. Individual tissues in rats were differentially inhibited in time and degree. The highest ACE inhibition in plasma and in tissues occurred within the first 2 h after gavage treatment with quinapril, 0.3 mg/kg. After 24 h, ACE was still inhibited by 25% in plasma, by 30% in the aorta, by 35% in the kidneys, and by more than 40% in cardiac atria and ventricles. Plasma and kidney tissues showed increasing ACE inhibition in a dose-dependent manner after oral dosing with quinapril. In the brain, only the structures outside the blood-brain barrier were inhibited after the administration of 0.1 mg/kg of quinapril. Similarly, testicular ACE was unaffected by quinapril. These results demonstrate a prolonged effect of quinapril on tissue ACE and suggest that ACE inhibition in the heart, vasculature, and kidneys may be of particular importance in pathologic states such as hypertension or heart failure.
JOURNAL OF CARDIOVASCULAR PHARMACOLOGY
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11368/1693693
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? 4
  • Scopus 74
  • ???jsp.display-item.citation.isi??? ND
social impact