Effects of interactions between progesterone and prostaglandin on uterine contractility in a perfused swine uterus model.

BACKGROUND/AIM: Uterine quiescence at the time of embryo transfer is a prerequisite for successful in vitro fertilization (IVF). This study assessed whether prostaglandin-induced contractions in the perfused swine uterus can be reduced by progesterone. MATERIALS AND METHODS: Fifty-eight non-pregnant swine uteri were perfused using an established extracorporeal perfusion model. Intrauterine pressure changes during perfusion with prostaglandin (PG) administration (PGE1, PGE2, PGF2α) and progesterone (1 pg/ml, 10 pg/ml, 25 pg/ml, 50 pg/ml) were assessed using an intrauterine double-chip microcatheter. RESULTS: The contraction-stimulating effect of PGs was clearly reduced by progesterone. Only PGE1 still triggered relevant contractions during continuous perfusion with progesterone solution, up to a concentration of 10 pg/ml. With PGE2 and PGF2α, a clear reduction of uterine contractility was observed even at at a progesterone concentration of 1 pg/ml. CONCLUSION: The extracorporal perfusion model of swine uteri shows that PG-induced contractions can be reduced in a dose-dependent manner by progesterone.

Chelidonium majus and its effects on uterine contractility in a perfusion model.

OBJECTIVE: The herbal agent celandine is thought to have mainly spasmolytic effects, but in the uterus it is regarded as promoting contractions, which can offer promising and innovative options for optimizing artificial reproduction. The aim of the present study was to investigate the effect of celandine on the uterine muscle, using a perfusion model of swine uteri. STUDY DESIGN: Sixteen swine uteri were perfused with Krebs-Ringer solution. Celandine (Chelidonium, Paverysat; Johannes Bürger Ysatfabrik Ltd., Bad Harzburg, Germany) was administered at increasing dosages. Intrauterine pressure (IUP) was recorded using an intrauterine double-chip microcatheter (Urobar 8 DS-F, Raumedic, Rehau AG & Co., Rehau, Germany). Differences in pressure (ΔP) and area under the curve (ΔAUC) after drug administration in the uterine body and uterine horn in the various dilution series were noted. A paired Student's t-test was used to evaluate differences between groups, with significance set at P<0.05. RESULTS: A significant initial increase in uterine activity was visible at each dosage. Inhibition of uterine activity was seen over longer periods of 5 and 10 min, particularly for a medium-dose range of 1-2mg/ml. At a dosage of 2mg/ml in particular, celandine almost always led to significant values. CONCLUSION: Following intra-arterial administration in a swine uterus perfusion model, celandine initially causes a significant increase in contractility, which is followed over time by a relaxation phase. This suggests interesting hypotheses on whether Chelidonium majus might be used to promote targeted sperm transport.

The perfused swine uterus model: long-term perfusion.

BACKGROUND: It has previously been shown that the viability of swine uteri can be maintained within the physiological range in an open perfusion model for up to 8 hours. The aim of this study was to assess medium- to long-term perfusion of swine uteri using a modified Krebs-Ringer bicarbonate buffer solution (KRBB) in the established open perfusion model. METHODS: In an experimental study at an infertility institute, 30 swine uteri were perfused: group 1: n = 11, KRBB; group 2: n = 8, modified KRBB with drainage of perfusate supernatant; group 3: n = 11, modified KRBB with drainage of perfusate every 2 h and substitution with fresh medium. Modified and conventional KRBB were compared with regard to survival and contraction parameters: intrauterine pressure (IUP), area under the curve (AUC), and frequency of contractions (F). RESULTS: Modified KRBB showed significantly higher IUP, AUC, and F values than perfusion with conventional KRBB. In group 3, the organ survival time of up to 17 h, with a 98% rate of effective contraction time, differed significantly from group 1 (P < 0.001). CONCLUSIONS: Using modified KRBB in combination with perfusate substitution improves the open model for perfusion of swine uteri with regard to survival time and quality of contraction parameters. This model can be used for medium- to long-term perfusion of swine uteri, allowing further metabolic ex vivo studies in a cost-effective way and with little logistic effort.