To investigate fetal development of protein C, a pregnant ovine model was used. Protein C was isolated from ovine plasma, and a polyclonal antibody was raised. Citrated plasma was obtained from undisturbed chronically catheterized fetal lambs. On Western blot, nonreduced adult ovine protein C had a molecular mass of 70 kD. Fetal ovine protein C was determined to have a molecular mass of 4 to 6 kD larger than the adult molecule. Crossed immunoelectrophoresis demonstrated slightly increased anodal migration of the fetal form. Isoelectric focusing demonstrated a decreased pI of the fetal molecule (4.45 versus 4.6). The ovine protein C molecules were deglycosylated with N-glycanase. Deglycosylated fetal protein C migrated more similarly to the adult form, although a portion of the fetal form persisted. These experiments demonstrate the first example of a unique fetal form of a vitamin K-dependent protein and are compatible with increased glycosylation of fetal ovine protein C. It is speculated that altered posttranslational processing may exist as a general process by which certain coagulation proteins are modified during fetal development. mRNA was isolated from maternal and fetal hepatic tissue and analyzed by NorthernThe hemostatic system of the fetus and neonate differs from that of the adult. Plasma concentrations of different coagulation factors achieve adult levels variably during maturation, such that by midgestation in the human, levels of factors V, VIII, fibrinogen, and the von Willebrand factor are within the normal adult range, whereas vitamin K-dependent factors 11, VII, IX, and X do not achieve adult means until several weeks to months postnatally (1).To date, the only fetal characteristic of the vitamin Kdependent proteins is the finding by Bovill et al. (2) of an increased production of des-carboxy prothrombin and protein C in term and preterm human neonates related to decreased activity of hepatic reductase. Protein C is a vitamin Kdependent coagulation zymogen that functions both to limit coagulation and to augment fibrinolysis (3). The ontogeny of protein C is of interest, because protein C seems to serve a hybridization. Fetal plasma concentration and hepatic mRNA for protein C were both 40% of normal maternal values from midgestation onward. At term, protein C mRNA increased to adult range ( p < 0.025), although plasma protein C concentration decreased slightly ( p < 0.001). A transition from fetal to adult protein C form was found beginning 6 d before term birth, with a doubling time of 24 h. These data are compatible with a gestationally determined maturation of ovine protein C. There was no evidence for very low plasma concentrations of protein C during normal fetal and neonatal development. Decreased plasma protein C concentration after birth associated with increased hepatic mRNA suggests increased turnover of protein C in the perinatal period. Further investigation of the transition from fetal to adult forms of protein C and altered hepatic mRNA expression will be necessary to understand,...

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The interests of the fetus generally are aligned with those of the pregnant woman. When they are not, the fetal best interests should be discussed, but respect for the autonomy of the pregnant woman and her bodily integrity should prevail. Gender bias and discrimination toward women should be avoided, and the circumstance of pregnancy should not be used as a reason to infringe upon or limit a competent woman’s rights. Evidence indicates that providing prenatal care and treatment in a supportive, rather than coercive way is the most effective way to promote both maternal and child health. Concerns about potential harm to the fetus related to maternal decisions must be evaluated in the context of the best medical evidence, including what is known and what is uncertain. Threats or legal coercion should not be used to force treatment, in particular, to impose cesarean delivery. Hospital guidelines can be developed to support a framework of shared decision-making in the situation of maternal-fetal conflict and provide guidance for compassionate conflict resolution. Pediatricians have an important role in informing the discussion about care and outcomes. At times, an ethics consult maybe helpful to mediate conflict resolution. Intervention by the courts is rarely appropriate or indicated and should be avoided.

We report the development and characterization of a system of primary culture of ovine fetal hepatocytes to aid in the understanding of the cellular regulation of fetal growth and metabolism with emphasis on amino acid metabolism and insulinlike growth factor gene expression and to allow comparison to in vivo studies. Hepatocytes were isolated from late gestation fetal lambs by in situ perfusion and collagenase digestion utilizing occlusion of the ductus venosus to limit intrahepatic shunting. Hepatocytes were cultured in media modified to mimic fetal concentrations of glucose, lactate, and amino acids. Ovine fetal hepatocytes in primary culture maintain the pattern of fetal amino acid production and utilization seen across the fetal liver in vivo. Specifically, there is a net production of serine and a net utilization of glycine. Cultured ovine fetal hepatocytes specifically increase tritiated thymidine incorporation in response to insulin and insulinlike growth factor II (IGF-II). IGF-II mRNA abundance is high and IGF-I mRNA is low in cultured ovine fetal hepatocytes as in the fetal sheep liver in vivo. These data demonstrate the successful isolation of ovine fetal hepatocytes that retain some of the characteristics of the ovine fetal liver while maintained in short-term culture.

To determine effects of diabetic gestation on plasma concentration of the coagulation regulatory protein, protein C, pregnant ewes were given glucose infusions to raise plasma glucose to twice baseline concentration or insulin infusions to lower glucose concentration to half baseline value. Control animals received no infusions. Concentrations of protein S, factor X, and antithrombin 111 were determined for comparison. Concentrations of glucose, insulin, and those above were determined thrice weekly for 2-9 wk. Short-term (8-12 h) infusions of glucose or insulin were performed to isolate their effects on concentration of protein C. Results were analyzed using a two-tailed t test, and protein C concentrations were further analyzed using a full linear mixed-effects model. In long-term infusions, hyperglycemia-induced hyperinsulinemia (mean insulin concentration 141 kU/mL) exerted negative effects on maternal concentrations of protein C [0.69 U/mL, n (number of samples) = 32, experimental versus 0.97 U/mL, t~ = 157, control], protein S (0.86 U/mL, n = 31, experimental versus 1.04 U/mL, n = 109, control), and factor X (0.89 U/mL, n = 31, experimental versus 1.08 U/mL, n = 109, control); it exerted no effects on antithrombin I11 (1.05 U/mL, tz = 23, experimental versus 1.04 U/mL, n = 32, control). The fetal lamb did not respond to chronic moderate hyperglycemia (mean 33 mg/dL) with a consistent change in insulin concentration (mean 10 I~C~. S I I . S 9 kU/mL): no coagulation protein changed. In contrast, fetal hypoglycemia resulted in decreased fetal plasma insulin (5 kU/mL t1er.slt.s 10 kU/ mL) and a corresponding increase in protein C (0.56 U/mL, tz = 17, experimental, tler.slcs 0.48 UImL, tz = 180, control) protein S (0.65 UImL, tz = 17, experimental versus 0.44 U/mL, 11 = 87, control), factor X (0.31 U/mL, t~ = 16, experimental ver.str.s 0.24 UImL, n = 86, control), and antithrombin I11 (0.96 U/mL, tl = 14, experimental versus 0.84 U/mL, PI = 32, control). Insulin concentration varied inversely with protein C concentration when all groups were considered together and accounted for 12% of the variability of protein C concentration in control ewes. Glucose was not found to exert an independent effect on protein C concentration within any study group but was significant when all groups were considered together. Short-term studies confirmed the long-term infusion findings in the maternal group with hyperglycemia-induced hyperinsulinemia. These studies indicate that hyperglycemia-induced hyperinsulinemia may predispose to hypercoagulability and thrombosis in the diabetic ewe and her fetus.