Relationship between the electrical activity of the oviduct and the uterus of the rabbit in vivo.

The electrical activity of the whole genital tract of the rabbit was recorded by means of chronically implanted electrodes after section of the uterotubal junction on one side. When the junction was intact, the activity of the isthmus and that of the proximal uterine horn occurred almost simultaneously, but uterine activity decreased after the junction was cut. During the preovulatory phase and also after administration of HCG, synchronos activity due to adrenergic drugs, smoke or oxytocin persisted on both sides of the uterotubal junction. Hypersensitivity of the isthmus and the proximal segment of the uterine horn was recorded on the cut side after ovariectomy. The concept of a local control mechanism in the region of the uterotubal junction with a positive control of the uterus by the oviduct is suggested.