Figure 1

(+)-Naloxone prevents LPS-induced PTD and fetal loss.

Pregnant B6 mice were administered LPS or PBS i.p. on gd 16.5, followed by (+)-naloxone or PBS i.p. on gd 16.5, 17.0, 17.5 and 18.0, then observed for PTD (delivered gd < 18.0) and autopsied at gd 18.5. (A) Dam outcomes at gd 18.5, classified as (i) pregnant (>1 live fetus); (ii) delivered early (gd 18.0–18.5); delivered preterm (gd < 18.0; >1 live pup), or (iv) delivered preterm, all pups dead. (B) The percentage of pregnant dams exhibiting PTD. (C) Fetuses and placentae dissected from a representative dam in each treatment group. Pups marked ‘*’ are judged non-viable. (D) Fetal outcomes at gd 18.5, classified as (i) resorbed; (ii) viable, in utero; (iii) viable, delivered preterm; (iv) non-viable, in utero, or (v) dead, delivered preterm. All pups born alive before gd 18.0 were dead within 36 h. (E) The number of viable pups per dam. Data in (A,B,D) are percentage analyzed by χ² test. Data in (E) are mean ± SEM analysed by two-way ANOVA. Number of pregnant dams per group is shown in parentheses. ^a,b,cDifferent letters indicate differences between groups, p < 0.05.