The ontogeny of innervation of the human pylorus.
OBJECTIVE
The aim of this study was to document the vagal innervation and expression of neuropeptides, neuronal nitric oxide synthase (nNOS), and neural cell adhesion molecule (NCAM) in the neuromuscular system of the developing human pylorus.


METHODS
Specimens of human pylorus (n = 54; age range, 8 weeks' gestation to 6 months postnatal) were studied. Vagal innervation was determined by Dil autofluorescence. A wide range of neuropeptides, NCAM, and the neural isoform of NOS were examined by immunohistochemistry.


RESULTS
Vagal innervation was first recognized in the myenteric plexus in the 12-week-old fetus as was vasoactive intestinal polypeptide (VIP) expression. Neuropeptides were present from 8 weeks' gestation and appeared to be expressed progressively from the adventitia toward the mucosa and showed an adultlike profile by 23 weeks' gestation. A craniocaudal pattern of expression was noted for VIP and nNOS. Alpha smooth muscle actin was expressed by muscle fibers of the muscularis propria from 8 weeks and the muscularis mucosae by 14 weeks. All the isoforms of NCAM examined were expressed from 8 weeks in the muscularis propria and by 12 weeks in the submucosa.


CONCLUSIONS
The expression of the antigens studied correlated with the gestational age and development of the pylorus.
Abel
R M
RM
Department of Histochemistry, Royal Postgraduate Medical School, Hammersmith Hospital, London, England.
Bishop
A E
AE
Moscoso
G
G
Spitz
L
L
Polak
J M
JM
D005314:Embryonic and Fetal Development; D005260:Female; D005333:Fetus / Q000294:innervation; D005753:Gastric Mucosa / Q000196:embryology / Q000294:innervation; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D009130:Muscle, Smooth / Q000196:embryology / Q000294:innervation; D009419:Nerve Tissue Proteins / Q000378:metabolism; D019006:Neural Cell Adhesion Molecules / Q000378:metabolism; D009479:Neuropeptides / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism; D052248:Nitric Oxide Synthase Type I; D011247:Pregnancy; D011708:Pylorus / Q000196:embryology / Q000294:innervation*; D014630:Vagus Nerve / Q000196:embryology*; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism
D009419:Nerve Tissue Proteins; D019006:Neural Cell Adhesion Molecules; D009479:Neuropeptides; D014660:Vasoactive Intestinal Peptide; C496320:NOS1 protein, human; D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I