ラット口腔粘膜における水チャンネルAquaporinの局在

The expression and localization of water channels, aquaporin (AQP) 1 and AQP3, in rat oral mucosa were examined by means of immunohistochemistry. AQP 1 was exclusively expressed in the capillary endothelial cells in the lamina propria, whereas the expression of AQP3 was recognized on the keratinocyte plasma membrane at the basal to prickle cell layer. It is considered that AQP3 is responsible for the hydration of the oral epithelium exposed to the environment of possible water loss and that AQP1 plays a role in providing water to them from subepithelial blood vessels. On the other hand, the junctional epithelium did not express AQP3, which was probably associated with sulcular fluid efflux. The aggregation of AQP-positive blood vessels just beneath the junctional epithelium seems to contribute to the generation of such an environment