AN AUTORADIOGRAPHIC METHOD FOR THE STUDY OF EGG TRANSPORT IN THE RABBIT FALLOPIAN TUBE

(0 A new technique is described in which 120-μ anionic resin spheres, impregnated with the radioactive gold isotope 198Au, are employed to simulate rabbit eggs. By their use, a study has been made of the pattern of egg transport in the Fallopian tube of the rabbit in vivo. (2) It has been shown that, in the first 8 hr after ovulation, the spheres have travelled 49% of the length of the tube. During the next 40 hr, movement down the tube is very slow until, at 48 hr after ovulation, the spheres are concentrated above the utero-tubal junction, 79% of the distance down the tube. (3) It has been possible to study the passage of the spheres into the uterus both at 56 and 64 hr after ovulation. Of the total number of spheres studied, 55% had passed into the uterus at the earlier and 90% at the later time. (4) Evidence is also included to show that the movement of the spheres reproduces the normal movement of eggs fairly closely. Their mean rate of progress is some 4% slower than the eggs, and this is due to a small proportion of the spheres lagging or