Quantitative Study of Pulmonary Endocrine Cells in Fetal, Postnatal and Adult Sheep

Abstract

ABSTRACT. Using light microscopic immunohistochemistry, neuron-specific enolase (NSE)-positive endocrine cells were quantitatively analyzed in the sheep lung during different stages of development from the canalicular stages to adulthood. In all stages, NSE-positive endocrine cells were usually located in the bronchi and bronchioles as solitary cells, although a few NSE-positive cell clusters, the socalled neuroepithelial bodies, were found in some places. The number of NSE-positive endocrine cells decreased with advanced stages of gestation. In the late alveolar stage, the number of NSE-positive endocrine cells reached its bottom during the fetal period. There was a gradual upturn after birth. The overall pattern of growth and differentiation of the endocrine cells is most likely species-related and depends on the state of airway development; the number of the endocrine cells of almost all animals, excluding the sheep, in relation to the size of the lung reaches a peak in the late fetal and early neonatal periods and decreases shortly thereafter. NSE-posit ive endocrine cells were also predominantly located in the large airways during the early stage of development (canalicular stage), and were found more frequently in the small peripheral airways towards the term. These results show the number of NSE-positive endocrine cells in t he sheep to be different from that seen in other species. KEY WORDS: endocrine cell, lung, sheep.

Expression of NSE and AFI in Fatal Lamb’s Lungs before and after Relieving Ureteral Obstruction

“…During lung development in lambs, NSEpositive cells exist beginning at 5 weeks of gestation. Thus, NSE is an indicator by which lung development can be monitored [5][6][7]. The expression of NSE in fetal lungs with ureteral obstruction has been the subject of a study [8].…”