کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9882230 1536549 2005 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Ca2+- and voltage-dependent inactivation of the expressed L-type Cav1.2 calcium channel
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
Ca2+- and voltage-dependent inactivation of the expressed L-type Cav1.2 calcium channel
چکیده انگلیسی
Ca2+-dependent regulation of the ion current through the α1Cβ2aα2δ-1 (L-type) calcium channel transiently expressed in HEK 293 cells was investigated using whole cell patch clamp method. Ca2+ or Na+ ions were used as a charge carrier. Intracellular Ca2+ was either buffered by 10 mM EGTA or 200 μM Ca2+ was added into non-buffered intracellular solution. Free intracellular Ca2+ inactivated permanently about 80% of the L-type calcium current. The L-type calcium channel inactivated during a depolarizing pulse with two time constants, τfast and τslow. Free intracellular calcium accelerated both time constants. Effect on the τslow was more pronounced. About 80% of the channel inactivation during brief depolarizing pulse could be attributed to a Ca2+-dependent mechanism and 20% to a voltage-dependent mechanism. When Na+ ions were used as a charge carrier, the L-type current still inactivated with two time constants that were 10 times slower and were virtually voltage-independent. Ca2+ ions stabilized the inactivated state of the channel in a concentration-dependent manner.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Archives of Biochemistry and Biophysics - Volume 437, Issue 1, 1 May 2005, Pages 42-50
نویسندگان
, ,