Corticotrophin-releasing hormone in lipopolysaccharide-stimulated term fetal membranes and amniotic fluid from term and preterm birth in African Americans and Caucasians

The objective of this study is to document differences in corticotrophin-releasing hormone (CRH), CRH receptor 1 (CRHR1), and CRH binding protein (CRHBP) gene expression in fetal membranes derived from African Americans and Caucasians in vitro in response to lipopolysaccharide (LPS) stimulation and to assess racial disparity in CRH concentrations in the amniotic fluid (AF) of women with spontaneous preterm birth (PTB). Fetal membranes (African American, n = 8; Caucasian, n = 8) at term, placed in an organ explant system, were stimulated with LPS. Microarray analysis documented differences in the mRNA expression pattern of CRH, CRHBP, and CRHR1 between races. CRH was measured in AF (a case [PTB]-control [term] study) and culture media. Between races, LPS significantly increased CRH and CRHR1 expression in African Americans and CRHBP in Caucasians, with no differences in controls. CRH was detectable only in LPS-stimulated African American membranes. AF CRH concentrations were higher in PTB compared with controls (P <.001), and no difference was noticed between races (P =.1). AF analysis did not document racial disparity in CRH concentrations in PTB. In fetal membranes, African Americans showed a higher expression and production of CRH in response to an in vitro stimulus.