||BK channels in human periodontal ligament fibroblasts
白鳥, 香理 ,
出張, 裕也 ,
宮崎, 晃亘 ,
平塚, 博義當瀬, 規嗣
札幌医学雑誌 = The Sapporo Medical Journal
38 , 2016-12-01 , 札幌医科大学医学部
The periodontal ligament ( PDL ) is the fibrous connective tissue which connects the cementum to the alveolar bone and consists predominantly of PDL fibroblasts as the main cellular component. PDL fibroblasts respond to mechanical stress via a specific signaling system with surrounding cells which in turn, results in the regulation of bone-matrix resorption and formation. Mechanical compression force is known to induce a reduction in the number of PDL fibroblasts. However, the precise mechanisms by which applied forces produce reactive changes in PDL fibroblasts remain poorly understood. Previous studies have reported that certain stretch-activated ion channels are able to convert extracellular mechanical stress into intracellular signals. In the present study, we evaluated stretch-activated ion channels in cultured human PDL fibroblasts. Patch clamp experiments revealed that cultured human PDL fibroblasts exhibit a stretch-activated potassium current with a single channel conductance of 275.4 pS. This potassium current is activated by membrane stretch and by an increase in the concentration of intracellular calcium. Our electrophysiological experiments indicated that the channel responsible for this current is likely to be a large conductance, calcium- and voltage-activated potassium channel ( BK channel ). Reverse transcription-polymerase chain reaction ( RT-PCR ) revealed the existence of BK channel mRNA in cultured human PDL fibroblasts. In summary, our results reveal that cultured human PDL fibroblasts exhibit functional BK channels.