Effect of aging and chronic angiotensin I converting enzyme inhibition on the endothelial function of the mesenteric arterial bed of the rat.
Endothelial function was studied in perfused mesenteric arterial bed preparations removed from 6, 12, 24, or 30 month-old, male, normotensive rats. Half of the animals were treated with a hypotensive dose of an angiotensin I converting enzyme (ACE) inhibitor (perindopril, 1 mg/kg/day, p.o.) from 6 months onwards. Disruption of endothelium produced a fall in baseline perfusion pressure in all animals except 30-month old controls, suggesting that the maintenance of baseline tone by endothelial vasoconstrictor(s) is impaired with age. Physiologic antagonism of norepinephrine-induced vasoconstriction by the muscarinic agonist carbachol was impaired in 30-month old controls. Norepinephrine-induced vasoconstriction increased following disruption of endothelium, suggesting that norepinephrine-induced release of endothelium-derived relaxing factor attenuates vasoconstriction. This mechanism was impaired in 30-month old controls. Chronic ACE inhibition postponed the age-related decrease in vasodilator and vasoconstrictor endothelial functions, either directly or indirectly via the hypotensive action of such treatment.
D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology*; D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology*; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D007211:Indoles / Q000494:pharmacology*; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D009569:Nitric Oxide / Q000378:metabolism; D020913:Perindopril; D051381:Rats; D011919:Rats, Inbred Strains; D014661:Vasoconstriction / Q000187:drug effects
D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents; D007211:Indoles; D009569:Nitric Oxide; D020913:Perindopril