[Immunohistochemical study on pulmonary neuroendocrine cells containing calcitonin gene-related peptide in sudden infant death syndrome]

To examine whether pulmonary neuroendocrine cells (PNEC) is associated with sudden infant death syndrome (SIDS), distribution and function of PNEC were investigated in infants from one to twelve months of age, including 19 cases with SIDS and 18 control cases without congenital heart disease and premature birth. In this study, lung tissue sections were immunostained with antibodies against chromogranin A (CGA) and calcitonin gene-related peptide (CGRP). Although the positivity of CGA in SIDS cases was not significantly different from that in control, the positivity of CGRP in SIDS cases was lower than that in control cases among one to four months old (p0.05). Our results suggest that respiratory and/or circulatory regulation of cases with SIDS is disturbed by reduction of CGRP expression, because CGRP is well known to be a vasodilator, a neurotransmitter and a promoter for proliferation of epithelium in airways.