Using the Isolated Rat Placenta to Assess Fetoplacental Hemodynamics.

Placental health is critical to fetal growth and maternal health during gestation. However, investigating placental flow in an ex-vivo isolated system where inflow is independently controlled has yet to be developed in the rat. Here, we describe a novel technique, isolated perfused placenta technique that allows for analysis of placental pressure outflow pressure, placental flow in rats at gestational day 20. Using this method, we successfully perfused placentas from dams and were able to observe increases in outflow pressure and flow as the inflow pressure to the placenta was increased in a step wise fashion. This method will help to advance the functional analysis of placental flow and therefore placental resistance and efficiency.

Role of neurokinin B in ovine puberty.

Puberty is the process whereby an individual acquires the ability to reproduce, and the attainment of puberty in a timely manner is critical for both humans and livestock. For livestock, the initiation of puberty at the appropriate time aids in increasing lifetime productivity, thus maximizing profitability for producers. For humans, particularly females, early or late puberty is associated with several adverse health outcomes, including polycystic ovary syndrome, obesity, metabolic syndrome, osteoporosis, and psychosocial distress. Therefore, characterizing the mechanisms responsible for puberty onset would have a significant impact on human and animal health. It has been postulated that a group of neurons in the arcuate nucleus of the hypothalamus may play a role in puberty onset. These neurons contain kisspeptin, neurokinin B (NKB), and dynorphin and are often called KNDy neurons. Although the role of kisspeptin in puberty onset has been heavily researched, the involvement of NKB and dynorphin is not well defined. This mini-review focuses on the role of NKB in the initiation of puberty in female sheep. Stimulation of the receptor for NKB, NK3R, elicits LH secretion in a GnRH-dependent manner in prepubertal ewes, and both functional and neuroanatomical changes to the NKB system, particularly within the preoptic area, appear to occur as female sheep transition from a prepubertal to an adult state. Thus, NKB is likely an important component of puberty onset in sheep, although its integration with other systems that impact the pubertal process, such as photoperiod and nutrition, remains to be elucidated.

In vitro progesterone production by luteinized human mural granulosa cells is modulated by activation of AMPK and cause of infertility.

BACKGROUND: Mural granulosa cells from IVF patients were provided by the West Virginia University Center for Reproductive Medicine in Morgantown, WV. The effect of adenosine monophosphate activated protein kinase (AMPK) activation, primary cause of infertility, age, BMI, and pregnancy outcome on production of progesterone were examined separately. METHODS: Isolated mural sheets from IVF patients (n = 26) were centrifuged, supernatant discarded, and the pellet re-suspended in 500 µl of DMEM/F12. Mural granulosa cells were plated at 10,000 cells/well in triplicate per treatment group with 300 µl DMEM/F12 media at 37 °C and 5% CO2 in a humidified incubator to permit luteinization. Four days after initial plating, cells were treated with either an AMPK inhibitor, DM; an AMPK activator, AICAR; or hCG. Cells were cultured for 24 h after treatment when medium was collected and frozen at -20 °C until assayed for P4 by radioimmunoassay. RESULTS: The AMPK activator, AICAR, inhibited P4 production (P < 0.001), whereas the AMPK inhibitor, DM, did not affect basal P4 (P < 0.05). Progesterone production increased when cells from patients whose primary cause of infertility was a partner having male infertility were treated with hCG compared to control (P = 0.0045), but not in patients with other primary infertility factors (P > 0.05). Additionally, hCG increased P4 production in patients between the ages 30-35 (P = 0.008) and 36-39 (P = 0.04), but not in patients ages 25-29 (P = 0.73). Patients with normal BMI had increased P4 production when treated with hCG (P < 0.0001), however there was no change in P4 production from cells of patients who were overweight or obese (P > 0.05). Cells from patients who became pregnant to IVF had greater P4 production when stimulated with hCG than those who did not become pregnant when compared to controls (P > 0.05). CONCLUSIONS: Understanding how AMPK activation is regulated in ovarian cells could lead to alternative or novel infertility treatments. Human mural granulosa cells can serve as a valuable model for understanding how AMPK affects P4 production in steroidogenic cells. Additionally, when stimulated with hCG, P4 production by mural granulosa cells differed among infertility type, age, BMI, and pregnancy outcome.