Endothelium-Derived Hyperpolarizing Factor (EDHF) Mediates Acetylsalicylic Acid (Aspirin) Vasodilation of Pregnant Rat Mesenteric Arteries

• Published in: International journal of molecular sciences 2021-09, Vol.22 (18), p.10162
• Main Authors: Helgadóttir, Helga, Tropea, Teresa, Gizurarson, Sveinbjörn, Mandalà, Maurizio
• Format: Article
• Language: English
• Subjects: Acetylsalicylic acid; Arteries; Arteriography; Aspirin; Calcium channels; Calcium ions; Channels; Endothelium; Experiments; Hypertension; Indomethacin; Laboratory animals; NG-Nitroarginine methyl ester; Nitric oxide; Nitric-oxide synthase; Paxillin; Potassium; Potassium channels (calcium-gated); Potassium chloride; Potassium conductance; Pre-eclampsia; Preeclampsia; Pregnancy; Pregnancy complications; Prophylaxis; Prostaglandin endoperoxide synthase; Smooth muscle; Vasodilation; Veins & arteries
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms221810162

Acetylsalicylic acid (aspirin) exhibits a broad range of activities, including analgesic, antipyretic, and antiplatelet properties. Recent clinical studies also recommend aspirin prophylaxis in women with a high risk of pre-eclampsia, a major complication of pregnancy characterized by hypertension. We investigated the effect of aspirin on mesenteric resistance arteries and found outdiscovered the molecular mechanism underlying this action. Aspirin (10−12–10−6 M) was tested on pregnant rat mesenteric resistance arteries by a pressurized arteriography. Aspirin was investigated in the presence of several inhibitors of: (a) nitric oxide synthase (L-NAME 2 × 10−4 M); (b) cyclooxygenase (Indomethacin, 10−5 M); (c) Ca2+-activated K+ channels (Kca): small conductance (SKca, Apamin, 10−7 M), intermediate conductance (IKca, TRAM34, 10−5 M), and big conductance (BKca, paxilline, 10−5 M); and (d) endothelial-derived hyperpolarizing factor (high KCl, 80 mM). Aspirin caused a concentration-dependent vasodilation. Aspirin-vasodilation was abolished by removal of endothelium or by high KCl. Furthermore, preincubation with either apamin plus TRAM-34 or paxillin significantly attenuated aspirin vasodilation (p < 0.05). For the first time, we showed that aspirin induced endothelium-dependent vasodilation in mesenteric resistance arteries through the endothelial-derived hyperpolarizing factor (EDHF) and calcium-activated potassium channels. By activating this molecular mechanism, aspirin may lower peripheral vascular resistance and be beneficial in pregnancies complicated by hypertension.