Serum induces the immediate opening of Ca2+-activated channels in quiescent human fibroblasts.
نویسندگان
چکیده
Application of fetal calf serum to quiescent human fibroblasts produces an immediate (3-20 s delay) increase in membrane conductance which lasts about 20-30 s. This conductance is strongly outwardly-rectifying and has a reversal potential between -45 and -10 mV. The conductance increase may also be induced by application of the Ca2+ ionophore A23187 while it does not occur when intracellular K+ is replaced by Cs+. It is concluded that this early effect of serum is due to the opening of Ca2+-activated channels. This permeability change will alter the membrane potential and thus possibly interact with other voltage-sensitive processes induced by serum growth factors.
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ورودعنوان ژورنال:
- FEBS letters
دوره 241 1-2 شماره
صفحات -
تاریخ انتشار 1988