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Updated: Aug 12, 2026

Videomorphometric Analysis of Hypoxic Pulmonary Vasoconstriction of Intra-pulmonary Arteries Using Murine Precision Cut Lung Slices
Published on: January 14, 2014
Effect of diadenosine phosphates on human umbilical vessels: novel platelet-derived vasoconstrictors
G Davies1, R J MacAllister, R G Bogle
1Department of Pharmacology and Clinical Pharmacology, St George's Hospital Medical School, London, UK.
Abstract:
The responses of human isolated umbilical artery to the novel platelet-derived mediators, diadenosine phosphates, P1,P5-di(adenosine-5')pentaphosphate (AP5A) and P1,P6-di(adenosine-5')hexaphosphate (AP6A) were studied in vitro. AP5A (1 nM-300 microM; n = 7) and AP6A (1 nM-30 microM; n = 5) produced transient concentration-dependent contractions. Responses to AP5A were unaffected by co-incubation with indomethacin (10 microM; n = 4), NGmonomethyl-L-arginine (L-NMMA; 300 microM; n = 4) and theophylline (1 microM; n = 5). These results demonstrate that diadenosine phosphates have constrictor effects on human blood vessels in vitro and are consistent with a role for these platelet-derived mediators in the regulation of blood vessel tone.
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