Epithelial Modulation on Guinea-pig Tracheal Smooth Muscle Tension to Contractile Agents / 대한마취과학회지

BACKGROUND: Asthma can be described as the hypersensitivity of the airway to various stimuli. Injury to tracheal epithelial cells could be the reason for tracheal hypersensitivity in asthma or upper respiratory infection. This study is based on the hypothesis that the dysfunction of the airway in asthma is caused by epithelial cell injury. METHODS: After isolating guinea-pig tracheal preparations, in order to examine the role of airway epithelium in response to smooth muscle, we measured the contractile responses to acetylcholine, carbachol, and histamine on the isolated epithelium-denuded or epithelium-intact guinea-pig tracheal preparations. When tracheal tones were stabilized, each contractile agent was added cumulatively to the organ baths to obtain concentration-response curves, and ED50 and ED95 were calculated. RESULTS: In both groups, tracheal tones increased in response to contractile agents, in concentration- dependent manners. In comparing both groups, the contractility of denuded trachea was increased by 10 7 and 10 6 M in acetylcholine, and by 10 6 M in histamine significantly. In denuded trachea, ED50 and ED95 increased significantly in response to both acetylcholine and histamine. However, they did not increase in carbachol. CONCLUSIONS: The removal of the epithelium increased the contractile responses to acetylcholine and histamine.

An Electron Microscopic Study on Cytoplasmic Organelles of the Cilicated Cell in Tracheal Epithelium in o-Chlorobenzylidene malononitrile (CS)gas exposed rat / 체질인류학회지

The effects of tear gas, o -chlorobenzylidene malononitrile (CS) on the cytoplasmic organelles were studied in the ciliated cell of rat tracheal epithelium. Albino rats (Sprague -Dawley strain), weighing about 150gm, were used as experimental animals. The experimental animals were exposed to 2.0 g/m 3 of CS gas for 20 minutes per day for the succesive 3 days. The experimental animals were sacrified at 1, 3, 6, 12 hours and 1, 3 and 5 days after final exposure to CS gas. Specimens obtained from the trachea were pre -fixed in 2% glutaraldehyde -2.5% paraformaldehyde and post -fixed in the 1% osmium tetroxide for electron microscopic study. The results obtained were as follows: 1. In 1 hour CS gas exposed group, rough endoplasmic reticulum with dilated cisternae, and mitochondria with disrupted double membrane in the ciliated cells are found. 2. In 3 hours and 6 hours CS gas exposed groups, dilated, segmented and sacculated cisterane of rough endoplasmic reticulum, mitochondria with dissolved cristae and disrupted double membrane, and Golgi complex with atrophied cisternae are observed in the ciliated cell. 3. In 12 hours CS gas exposed group, some mitochondria with swollen cristae is found in the ciliated cell. 4. In 1 day CS gas exposed group, mitochondria with dissolved cristae, Golgi complex with hypertrophied cisternae, and autophagic vacuole are found. 5. In 3 day and 5 day CS gas exposed groups, numerous mitochondria, well -developed rough endoplasmic reticulum, and supranuclear Golgi complex are found in ciliated cell. The results of the present study suggest that the o -chlorobenzylidene malononitrile (CS) gas is cytotoxic to the ciliated cells in tracheal epithelium inducing some degenerative changes, which are recovered with the lapse of time.

Immunohistochemical Study on Cytokeratin Expression in Tracheal Epithelium of Human Fetus / 체질인류학회지

Trachea is lined by a pseudostratified epithelium which usually expresses a complex mixture of stratified as well as simple epithelial-type cytokeratins. In the present work, the cytokeratin expressions was studied immunohistochemically in the tracheal epithelium and gland of human fetus at 14, 26 and 32 weeks of gestation. The primary antibodies used were CK7, 8, 10, 14, 18, AE8, 5D3, MNFl16 and AE3. In PAS-hematoxylin stain, the tracheal eithelium was composed of pseudostratified ciliated columnar type and consisted of surface, intermediate and basal layers regardless of gestational ages. The PAS positive cells, however, were decreased in number in proportion to gestational ages. The tracheal gland was not fully differentiated at 14 weeks of gestation, and had well differentiated secretory portions consisting mucous and serous cells at 26 and 32 weeks of gestation. The mucous cells and luminal border of the duct were positive for PAS stain. The tracheal eithelium showed different immunoreactivity between cartilageous and membranous portions. In general, CK7 and 5D3 were expressed in surface cells, AE8 in intermediate cells, and MNFl16 and AE3 in the cells of all layers. At 14 weeks of gestation, the tracheal epithelium immunoreacted for CK7, AE8, 5D3, MNFl16 and AE3. The premordium of tracheal gland was positive for 5D3, MNFl16 and AE3. The tracheal epithelium at 26 and 32 weeks of gestation showed same staining properties to those at 14 weeks of gestation. The duct cells at 26 weeks of gestation were immunoreactive for CK7, 8, 14, 18, AE8, 5D3, MNFl16 and AE3, and those at 32 weeks of gestation were immunoreactive for CK7, 14, 5D3, MNFl16 and AE3. The acinar cells at 26 and 32 weeks of gestation were positively stained for CK7, 8, 18, 5D3, MNFl16 and AE3. These results suggest that CK7 and 5D3 may serve as useful markers for mature cilated cells, AE8 (CKl3) for immature ciliated cells, and CKl4 for duct cells in tracheal epithelium and gland.

Electron Microscopic Study on Differentiation of Tracheal Epithelium in Human Fetus / 체질인류학회지

The human trachea is normally lined by a pseudostratified ciliated columnar epithelium where ciliated, goblet, intermediate and basal cells are mainly represented. However the fetal tracheal epithelium was found to be composed of ciliated, non-ciliated and basal cells. The present study was designed to characterize the development of ciliated cells in the fetal trachea at mid (19 weeks) and last (32 weeks) trimester of gestation. At 19 weeks of gestation, the tracheal epithelium, 35 µm in height, was composed of surface, intermediate and basal layers. The surface cells were subdivided into ciliated, immature ciliated, non-ciliated, granule containing and goblet cells. The ciliated cells covered approximately half of the luminal surface area. The immature ciliated cells contained basal bodies, but the apical membrane was not invested with cilia. The granule containing cells contained numerous dense granules, 0.3-0.7 µm in diameter, in the apical cytoplasm. The goblet cells contained less electron dense granules, 1-2 µm in diameter, in the apical cytoplasm. The cells in intermediate layer were relatively undifferentiated and contained poorly developed organelles. Submucosal gland were well differentiated and were composed of the mucous and serous cells. At 32 weeks of gestation, the tracheal epithelium, 50µm in height, was also composed of surface, intermediate and basal layer. The surface cells were composed of ciliated, non-ciliated and goblet cells. The ciliated cells, dominant type of surface cells, were subdivided into mitochondria-rich cells (type I) and smooth endoplasmic reticulum-rich cells (type II). The non-ciliated cell were of three subtypes : mitochondria-rich cells (type A), glycogen and microfilament-containing cells (type B) and cells with bulging apical surface into the lumen (type C). Small granule containing cell appeared in the basal layer. These cells contained clear vesicles, 50 ㎚m in diameter, and dense granules, 100-300 ㎚m in diameter. Submucosal gland were well developed and consisting of mucous, serous and myoepithelial cells. These results indicate that the cell populations of the tracheal epithelium at late stage of pregnancy have essential features similar to those of adult. and show that the different steps of ciliogenesis could be identified.

HETEROGENEITY OF TRACHEAL EPITHELIAL GOBLET CELLS OF MONKEY / 解剖学报

The reactions of 8 lectins with tracheal epithelial goblet cells of Rhesus monkeyshowed the heterogeneity of the cells.The heterogeneity appeared on the differentcomposition of sugar chains in the secretory mucin.The mucin of all goblet cellscontained unequal amount of terminal ?-D-galactose,?-D-mannose and sialic acid aswell as pre-terminal-?-D-galactose and/or ?-D-galactose-(1→3)-N-acetylgalactosa-mine.Only part of goblet cells had variable amount of ?-L-fucose in the secretorymucin.The compositions of sugar chains of the secretory mucin between monkeyand human have significant difference.