Management of human placental arterioles
This study was approved by the Clinical Trial Ethics Committee of the Affiliated Hospital of Southwest Medical University (registration number: KY2019039). All work was undertaken according the provisions of the Declaration of Helsinki. All patients signed informed consent for specimen collection. Ten single pregnant women diagnosed with severe preeclampsia were selected as the experimental group (SP), and 10 single pregnant women with normotensive pregnancy were chosen as the control group (NP). All patients were hospitalized and delivered by either vaginal delivery or cesarean section in the Department of Obstetrics in our hospital from May 2020 to May 2021. Inclusion criteria for the SP group were based on the American College of Obstetricians and Gynecologists (ACOG) Guidelines[12]. All subjects were excluded from the study if they had chronic hypertension, kidney disease, cardio-cerebrovascular disease, severe liver and kidney function impairment, other basic diseases, systemic diseases or other pregnancy complications. Patients who had histories of smoking, alcohol abuse, syphilis, hepatitis virus and human immunodeficiency virus were also excluded. We collected patient demographic and clinical characteristics, such as maternal age, gestational age and blood pressure (Table 1). After the placenta was delivered, the fetal membrane was immediately stripped under sterile conditions, and 3-5 pieces of placental tissue with small placental arterioles near the edge of the placenta, approximately 4*1*1 cm3 in size, were extracted and placed in the prepared specimen box, which was immediately transferred to the laboratory under low temperature. Then, the perivascular connective tissue was rapidly and gently removed under a microscope, taking care to minimize the damage to the blood vessels, and vessels with diameters of approximately 0.1-0.2 cm and lengths of approximately 2-3 cm were separated. Some of the isolated blood vessels were frozen in liquid nitrogen and then quickly transferred to a freezer at -80 °C for cryopreservation, and these samples were used for subsequent PCR and Western blot analyses. The rest were fixed in 4% paraformaldehyde, and the specimens were used for subsequent HE staining and immunohistochemical analysis.