Effects of kinins on isolated blood vessels. Role of endothelium

Abstract

Bradykinin (BK) and des-Arg9-BK were used to determine whether the stimulatory and inhibitory actions of the kinins in various isolated vessels require the presence of endothelium and may be mediated by arachidonic acid metabolites. It was found that the presence of intact endothelium is required only for the relaxation of the dog common carotid artery in response to bradykinin. Stimulatory actions of both BK and des-Arg9-BK in arterial (rabbit aorta) and venous (rabbit jugular and mesenteric vein) smooth muscle do not require the presence of endothelium. Inhibition of the arachidonic acid cascade at various levels affects the relaxing action of acetylcholine (rabbit aorta and dog common carotid artery) while being inactive against both the relaxing (dog common carotid artery) and contractile actions (rabbit aorta, rabbit jugular and mesenteric veins) of bradykinin and des-Arg9-BK. Inhibitors of the arachidonic acid cascade also do not affect the inhibitory action of isopropylnoradrenaline on the rabbit aorta. The present results indicate that stimulant actions of kinins in isolated vascular smooth muscles do not require the presence of endothelium. Endothelium is required for the inhibitory actions of acetylcholine and bradykinin but not for that of isopropylnoradrenaline on the dog carotid artery. Moreover, the inhibition of arachidonic acid metabolism only affects the response of isolated vessels to acetylcholine. The present results suggest that several mechanisms may be involved in the inhibition of vascular tone by vasodilators.

Effects of bradykinin and leukotrienes B4 and D4 on the bovine brochial arteryin vitro: Role of the endothelium

“…4). These observations are consistent with the finding that bradykinin dilates the bronchial circu-lation of the ventilated dog lung [9], as well as the reported relaxation of precontracted arteries with endothelium from various species [17,18,28]. The lack of effectiveness of bradykinin when administered to the bath fluid surrounding the bronchial arteries is consistent with endothelial mediation of the bradykinin-induced relaxation.…”

“…Bradykinininduced endothelium-dependent relaxations in canine arteries were not blocked by indomethacin [17,18,28], flurbiprofen [18], eicosatetraynoic acid (ETYA) [28], or mepacrine [28]. However Chand and Altura [17] reported that in canine renal arteries, NDGA, ETYA and BW755C inhibited or transformed relaxant responses to bradykinin into contractile responses.…”

Kinin B2 receptor‐mediated contraction of tail arteries from normal or streptozotocin‐induced diabetic rats

“…The B 1 receptor-mediated vasoconstriction is endothelium independent and not mediated by prostaglandins (Regoli et al, 1982). The vascular responses to B 2 receptor activation, however, have been controversial.…”

Einflüsse von Bradykinin auf die systemische und die pulmonale Hämodynamik am Menschen

“…Da die Endothelien der arteriellen Gef/ige spezifische Bradykininrezeptoren (B2-Typ) besitzen, kann vermutet werden, dab Bradykinin direkt fiber die Rezeptoren seine Wirkung entfaltet [23,24]. Die reflektorische Herzfrequenzsteigerung bedingte einen Anstieg des Herzminutenvolumens, der jedoch nicht ausreichte, um den Blutdruckabfall aufzuhalten.…”