Summary: | The Fallopian tubes are organs of transport and the tubal fluid nourishes the embryo during this time. Their role, however, has largely been neglected since the development of in vitro fertilisation. Studies of tubal physiology have been limited by the relative inaccessibility of the tubes, problems with collecting neat tubal fluid and difficulties in developing tests which reliably assess tubal function rather than tubal patency. This thesis sets out to validate the technique of in vitro vascular perfusion of the Fallopian tubes and to demonstrate that it is a reproducible technique which can be used for studying tubal physiology and of defining the environment to which the gametes and pre-implantation embryo are exposed. These experiments show that the Fallopian tubes can be perfused for up to 2 hours without damage and loss of viability. In this time, sufficient fluid can be collected for analysis of glucose, pyruvate, lactate and amino acids. This is the first report of amino acid composition in human tubal fluid. Using the validated technique, tubal fluid production was shown to vary with the menstrual cycle. Greater volumes were produced in the proliferative and early secretory phases. Fluid production was also stimulated by isoproterenol and suppressed by dibutyryl cyclic-AMP. The concentrations of glucose, pyruvate and lactate in native tubal fluid were 0.93 mM (+/- 0.15), 0.28 mM (+/-0.1), and 6.5 mM (+/- 0.6) respectively. All 17 amino acids tested were present in low concentrations with alanine and arginine the most concentrated irrespective of the phase of the menstrual cycle. Tubal muscle activity in response to isoproterenol was studied by monitoring isometric contractions via a Gallenkamp 2-channel recorder, Isoproterenol reduced the frequency of muscle contractions in both longitudinal and circular layers irrespective of the hormonal status of the women. Amplitude of contractions in the circular layer was increased by isoproterenol.
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