Fig. 5. NO Donor effects on vascular morphology and NOS distribution. The vascular morphology of NOC18-treated conceptuses was evaluated by PECAM1 staining at 9.5 dpc: (A) control and (B) NOC18. Morphometric analysis of images from PECAM1-stained yolk sacs showing vessel diameter distribution (C). Representative western blot of the effect of a NO donor on NOS protein distribution at 8.5 dpc (D). Experiments were repeated at least five times.