Fig. 4. Vagal-to-sacral heterotopic graft, E7. (A) In the colorectum, QCPN+ cells encircled the gut, within the region external to the circular muscle layer, corresponding to the myenteric plexus (mp) being heavily colonised. Internal to the circular muscle layer, in the region corresponding to the submucosal plexus (smp), QCPN+ cells were more sparsely distributed. (B) In the cecal region, the intestine wall and cecal buds were colonised by transplanted vagal NCC. In the intestine, QCPN+ cells were present on either side of the circular muscle wall, while in the cecal buds, immunopositive cells were only present external to the circular muscle layers (arrowheads). (C) In the post-umbilical intestine, QCPN+ cells were present external to the circular muscle layer (arrowheads). Note that in all regions, the nerve of Remak (R) was poorly developed compared with controls. (A',B',C') In control embryos at E7 no sacral NCC were present within any regions of the gut wall. However, the nerve of Remak was well developed and large ganglia (R) were apparent in transverse sections. Scale bars: 100 µm.
