The transport of gametes and embryos through the mammalian oviduct is controlled by two active mechanisms: ciliary undulations and smooth muscle contractility. While much is known about the cilia-mediated transport mechanism, there is little information about the muscle-mediated transport mechanism. To quantitate the contractile activity of the rabbit oviductal musculature two complementary approaches will be used to measure the frequency of contractile events and determine the direction, distance, and velocity of contraction propagation. First, video tapes will be made of oviduct contractility using anesthetized animals whose oviducts have been isolated in an abdominal observation chamber; data will be acquired by digitizing the video records. Second, data will be obtained from conscious rabbits whose oviducts have been chronically instrumented with extraluminal optoelectronic contraction sensors. These data will be acquired throughout the coitus, luteinizing hormone, or human chorionic gonadotropin induced periovulatory periods to quantitatively compare the affects of each of the ovulation inducing stimuli on oviduct contractile activity. The data will be acquired using a microcomputer that converts the analog contraction signal to digital data. These data will then be analyzed to provide detailed information about the contractile events in all regions of the oviduct. Oviduct contractile activity during the coitus-induced periovulatory period will also be compared to contractile activity from animals given estradiol treatments known to affect embryo transport and to animals whose oviducts have been denervated with 6-hydroxydopamine. These experiments are designed to elucidate how these treatments affect the muscle-mediated transport mechanism and test a new descriptive model that describes how the oviductal musculature controls gamete and embryo transport. Finally, these data will be used to develop and test a formal mathematical model of gamete and embryo transport and from this develop a computer simulation of the oviduct. This model and its simulator will then be used to predict gamete and embryo transport rates and the position of gametes and embryos within the oviduct under different conditions. These experiments should lead to a better understanding of oviductal physiology that should be useful in studying the etiology of endometriosis, understanding idiopathic infertility, or even aid in the development of new contraceptive techniques.
