Pregnancy-induced alterations of neurogenic constriction and dilation of human uterine artery

The results of a study of the responses to electrical field stimulation (EFS) of perivascular nerves in human uterine arteries and the effect of pregnancy on these responses demonstrate that the arteries respond to EFS with contraction and relaxation and that these responses may be mediated, respectively, by norepinephrine and, in part, by nitric oxide released from periarterial nerves.