Nestin expression in neonatal and adult rat vessels. Nestin, CD31 and smooth muscle α-actin (SMA) staining of (Panels A & B) the neonatal aortic arch, (Panel C) adult aortic arch, (Panel D) adult thoracic region and (Panels E & F) adult rat carotid artery. The arrow indicates the luminal side and the nucleus identified by DAPI (blue fluorescence). (Panel G) Nestin expression was greatest in the aortic arch (AA) as compared to the thoracic (TA) and abdominal (AB) regions of the adult rat aorta, whereas CD31, eNOS and smooth muscle α-actin protein levels were unchanged. (*) Denotes P < 0.05 versus AA and protein levels were normalized to GAPDH.