Effect of sympathetic nerve stimulation on the uterine vascular bed

Sympathetic adrenergic (vasoconstrictor) nerve fibers are distributed widely to the vasculature of the gravid. ovine uterus. During pregnancy, resting adrenergic vascular tonus is minimal but this innervation is capable of producing marked uterine vasoconstriction from appropriate stimuli. Sympathetic cholinergic (vasodilator) innervation of the gravid uterine vascular bed has not been demonstrated.