Effect of copper and plastic intrauterine devices on the norepinephrine content of rabbit oviduct and uterus.

An intrauterine device (IUD) consisting of either a plain or a copper-coated polyethylene catheter was inserted in one of the uteri of rabbits. Sham-operated uteri served as controls. The norepinephrine (NE) content was compared only between uteri within the same animal. Both copper and plastic IUDs markedly reduced the NE content in the uterus, but not in the oviduct, within 1 week after insertion. NE in both organs was present exclusively in the adrenergic nerve system. There was no difference in the action of the two types of IUDs. The effect of an IUD was probably eliminated by interruption of the preganglionic nerve connections. The results showed that the uterine adrenergic neurons are influenced by the presence of an IUD.