Phenylephrine hold stable the constriction of the vessels for enough time necessary to observe clearly the action of the G1 showed in traces B and D respectively for NP and P. Several experiments were done and the data were summarized in Fig 1E that suggested G1, tested in the range (10 -12 –10 -6 M), induced vasodilation in a concentration-dependent manner in preconstricted radial uterine arteries from both NP and P rats.
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