Distribution of heme oxygenase-2 in nerves and interstitial cells of Cajal in the normal pylorus and in infantile hypertrophic pyloric stenosis.
BACKGROUND
Interstitial cells of Cajal (ICCs) are pacemaker cells, which are of fundamental importance in regulating gastrointestinal motility. Recent evidence suggests that carbon monoxide is a neurotransmitter involved in neurotransmission between ICC and smooth muscle cells. Heme oxygenase-2 (HO-2) is the major physiological mechanism for the generation of carbon monoxide in the enteric nervous system.


OBJECTIVE
To investigate the immunocolocalization of HO-2 and ICCs in the normal pylorus and in infantile hypertrophic pyloric stenosis (IHPS).


METHODS
Specimens from 18 infants with IHPS and 8 control specimens were examined using double-immunostaining with c-Kit and HO-2 antibodies. The immunolocalization was detected with the help of confocal laser scanning microscopy.


RESULTS
Abundant HO-2 immunoreactivity was found in ICCs in the smooth muscle layer of normal pylorus. There was a decrease in the number of ICCs and lack of HO-2 immunoreactivity in ICCs in IHPS.


CONCLUSIONS
The results of the present study provide the first evidence for the presence of HO-2 in ICCs in the normal human pylorus. The lack of ICCs and HO-2 in IHPS suggests impaired intracellular communication between ICCs and smooth muscle cells, contributing to motility dysfunction in IHPS.
Piotrowska
Anna Piaseczna
AP
Children's Research Centre, Our Lady's Hospital for Sick Children and University College Dublin, Dublin, Ireland.
Solari
Valeria
V
Puri
Prem
P
D017615:Enteric Nervous System / Q000201:enzymology*; D005260:Female; D006419:Heme Oxygenase (Decyclizing) / Q000378:metabolism*; D006801:Humans; D006984:Hypertrophy; D007150:Immunohistochemistry; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D018613:Microscopy, Confocal; D019009:Proto-Oncogene Proteins c-kit / Q000032:analysis; D011707:Pyloric Stenosis / Q000201:enzymology* / Q000473:pathology; D011708:Pylorus / Q000166:cytology / Q000201:enzymology*
D006419:Heme Oxygenase (Decyclizing); C105245:heme oxygenase-2; D019009:Proto-Oncogene Proteins c-kit