- 作者: F. Savignan; B. Ballion; M.F. Odessa; M. Charveron; P. Bordat; B. Dufy
- 作者服務機構: Laboratoire de Physiologie et de Physiopathologie de la Signalisation Cellulaire, Universite Bordeaux2, Bordeaux, and Pierre Fabre Dermo-Cosmetique, Vigoulet Auzil, France
- 中文摘要: --
- 英文摘要: We have used the human calcium- and temperature-dependent(HaCaT) keratinocyte cell line to elucidatemechanisms of switching from a proliferating to a differ-entiating state. When grown in low calcium medium(<0.1 mM HaCaT cells proliferate.However, an increasein the calcium concentration of the culture medium, [Ca2+]o, induces growth arrest and the cells start to differ-entiate. Numerous studies have already shown that theincrease in [Ca2+]o results in acute and sustained in-creases in intracellular calcium concentration,[Ca2+]i.Wefind that the Ca2+-induced cell differentiation of HaCaTcells is also accompanied by a significant decrease inmitochondrial membrane potential, DeltaPsi.By combin-ing patch-clamp electrophysiological recordings and mi-crospectrofluorimetric measurements of DeltaPsi on sin-gle cells, we show that the increase in [Ca2+]i led to Del-taPsi depolarization.In addition,we report that tetraeth-ylammonium (TEA), a blocker of plasma membrane K+channels, which is known to inhibit cell proliferation,and4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid(DIDS),a blocker of plasma membrane Cl-channels, also affectDeltaPsi.Both these agents stimulate HaCaT cell differ-entiation.These data therefore strongly suggest a directcausal relationship between depolarization of DeltaPsiand the inhibition of proliferation and induction of differ-entiation in HaCaT keratinocytes.
- 中文關鍵字: --
- 英文關鍵字: --