Uptake of 3H-norepinephrine in different segments of the human non-pregnant and pregnant uterus.

Tissue specimens from uterine cervix and corpus of non-pregnant and pregnant women were incubated in vitro in the presence of 3H-norepinephrine. The uptake in the cervix exceeded those of the lower and upper segments of the corpus, and this difference was most pronounced at term pregnancy. The neuronal uptake in the cervix constituted approximately 80% of the total uptake and was higher than in isthmus and fundus (50 and 20%, respectively). The results favour the notion that cervical nerves remain functionally intact throughout pregnancy and support previous histochemical studies demonstrating a segmental difference in uterine innervation and a partial denervation of the myometrium at term.