Article

Inflammatory response to repetitive umbilical cord occlusions with worsening acidosis in the near term ovine fetus

Department of Obstetrics and Gynecology, Lawson Health Research Institute, University of Western Ontario, London, Canada.
American journal of obstetrics and gynecology (Impact Factor: 3.97). 11/2009; 202(1):82.e1-9. DOI: 10.1016/j.ajog.2009.08.020
Source: PubMed

ABSTRACT We hypothesized that repetitive umbilical cord occlusions (UCOs) with worsening acidosis will lead to a fetal inflammatory response.
Chronically instrumented fetal sheep underwent a series of UCOs until fetal arterial pH decreased to <7.00. Maternal and fetal blood samples were taken for blood gases/pH and plasma interleukin (IL)-1B and IL-6 levels. Animals were euthanized at 24 hours of recovery with brain tissue processed for subsequent measurement of microglia and mast cell counts.
Repetitive UCOs resulted in a severe degree of fetal acidemia. Fetal plasma IL-1B values were increased approximately 2-fold when measured at maximal fetal acidosis and again at 1-2 hours of recovery. Fetal microglia cells were increased approximately 2-fold in the white matter and hippocampus, while mast cells were increased approximately 2-fold in the choroid plexus and now evident in the thalamus when analyzed at 24 hours recovery.
Repetitive UCOs leading to severe acidemia in the ovine fetus near term will result in an inflammatory response both systemically and locally within the brain.

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