The ACh‐induced contraction in rat aortas is mediated by the Cys Lt₁ receptor via intracellular calcium mobilization in smooth muscle cells

Abstract

1 Our previously published data indicate that an endogenously produced 5-lipoxygenase metabolite can strongly contract isolated endothelium-preserved rat aortic strips when cyclo-oxygenase isoenzymes are inhibited. Therefore, we decided to investigate if cysteinyl-containing leukotrienes (Cys Lts) are involved in this endothelium-dependent contraction. 2 The isometric contraction of endothelium-preserved rat aortic strips was recorded in preparations preincubated with 5 mM indomethacin and precontracted with phenylephrine, adjusting resting tension at 0.7 g. Acetylcholine (ACh) contracted control strips. Montelukast and MK-571, selective type 1 Cys Lts receptor (Cys Lt 1 ) antagonists and the Cys Lt 1 /Cys Lt 2 (type 2 Cys Lts receptor) antagonist BAYu9773 dose-dependently prevented ACh-induced contraction, their IC 50 s being 2.2, 3.1 and 7.9 nM respectively. The leukotriene B4 receptor antagonist U75302 was far less potent (IC 50 1.5 mM).

Adipose-derived stem cells decrease pain in a rat model of oxaliplatin-induced neuropathy: Role of VEGF-A modulation

“…In all experiments, only cells at P2 of culture were used. Detailed procedures used for rASCs, rat coronary endothelial cells (Failli et al, 2000) and rat aortic smooth muscle cells (Mazzetti et al, 2003) were described in the Supplementary material.…”

Effect of 5-lipoxygenase blockade on blood pressure and acetylcholine-evoked endothelium-dependent contraction in aorta from spontaneously hypertensive rats

“…The leukotriene synthesis inhibitor and cysLT antagonist attenuate ACh-induced contraction in rabbit coronary artery [18]. More recently, Mazzeti and colleagues [19] reported that, in the presence of indomethacin, cysLT receptor antagonists blocked the endothelium-dependent contraction to ACh in aorta from normotensive rats.…”

Relaxant Effect of a Water Soluble Carbon Monoxide-Releasing Molecule (CORM-3) on Spontaneously Hypertensive Rat Aortas

“…After 60 min of stabilization, the absence of endothelium was tested as previously reported [18], and cumulative concentration-response curves of AT-II or ET-1 were performed in different aortic preparations. Then, strips were extensively washed, re-stabilized and precontracted using the maximal contracting dose of AT-II or ET-1 (100 % of contractile response).…”