Figure 2.

Maternal inflammation increases placental TPH1 enzymatic activity and ex vivo 5-HT output to the fetus. A, Twenty-four and 48 h after saline (control) or poly(I:C) (2 mg/kg) injections at E12, TRP to 5-HTP conversion, which reflects TPH enzymatic activity, was measured in placentas (TPH1) and fetal hindbrains (TPH2). Maternal inflammation induces a significant increase in TPH1 activity over saline (control) level (measured in placental extracts from saline injected dams) at 48 h only. TPH2 activity in the hindbrain is unchanged at both the 24 and 48 h time points. *p < 0.05, two-way ANOVA with Bonferroni correction. B, Ex vivo placental perfusions showing that significantly more 5-HT is synthesized and released from the placenta 48 h after maternal poly(I:C) exposure compared with saline (control) exposure. *p < 0.05, unpaired t test with Holm–Sidak correction. Error bars indicate SEM percentage change (A) or SD (B). n = 3 (A) or n = 1 (B) placentas per dam.