Morphometric evaluation of PGP9.5 and NCAM expressing nerve fibers in colonic muscle of patients with Hirschsprung's disease.
A quantitative assessment of the density of the protein gene product 9.5 (PGP9.5), the neural cell adhesion molecule (NCAM), and the low-affinity nerve growth factor receptor (NGFR) expressing nerve fibers in the circular muscle layer in the colon was carried out by morphometric analyses from 13 patients with Hirschsprung's disease (HD). The difference in the nerve fiber density between the ganglionic and aganglionic segments was compared by calculating the ratio of the sum of the areas occupied by positively stained nerve fibers per unit area of the muscle after immunohistochemical staining on paraffin embedded tissue sections using computer software. There was an obvious difference in the density of the PGP9.5 stained nerve fibers between the ganglionic (0.0380 +/- 0.0171) and aganglionic segments (0.0143 +/- 0.01661). The NCAM-positive nerve fibers were fewer in number than those of both the PGP9.5-positive fibers and NCAM-positive fibers, which were also markedly lower in number in the aganglionic segment (0.0066 +/- 0.0076) than in the ganglionic segment (0.0230 +/- 0.0195). Immunostaining for low-affinity NGFR revealed much fainter staining in the ganglionic and aganglionic segment without a statistically significant difference in their density. Considering the fact that PGP9.5 is a very sensitive marker for nerve fibers, the results of this study reaffirm the innervation failure of the proper muscle in HD. The decreased NCAM expression level in the aganglionic segment appears to be caused not by the selective down-regulation of NCAM expression among the nerve fibers but by a markedly reduced number of nerve fibers.
Oh
Jung Tak
JT
Department of Pediatric Surgery, Yonsei University College of Medicine, C.P.O. Box 8044, Seoul 120-752, Korea.
Han
Ai Ri
AR
Yang
Woo Ick
WI
Han
Seok Joo
SJ
Choi
Seung Hoon
SH
Hwang
Eui Ho
EH
D003106:Colon / Q000294:innervation*; D006627:Hirschsprung Disease / Q000473:pathology*; D006801:Humans; D009130:Muscle, Smooth / Q000294:innervation*; D009412:Nerve Fibers / Q000737:chemistry* / Q000473:pathology; D019006:Neural Cell Adhesion Molecules / Q000032:analysis*; D020800:Receptor, Nerve Growth Factor / Q000032:analysis; D013869:Thiolester Hydrolases / Q000032:analysis*; D043222:Ubiquitin Thiolesterase
D019006:Neural Cell Adhesion Molecules; D020800:Receptor, Nerve Growth Factor; D013869:Thiolester Hydrolases; D043222:Ubiquitin Thiolesterase