کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10954247 | 1097869 | 2008 | 10 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Late-stage alterations in myofibrillar contractile function in a transgenic mouse model of dilated cardiomyopathy (Tgαq*44)
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
Troponin I - تروپونین ICardiac function - عملکرد قلبیPhosphorylation - فسفریلاسیونTransgenic mouse - موش ترانسژنیکheart failure - نارسایی قلبیG proteins - پروتئین GProtein kinase A (PKA) - پروتئین کیناز A (PKA)Protein kinase C - پروتئین کیناز سیDilated cardiomyopathy - کاردیومیوپاتی دیلاته، کاردیومیوپاتی کامل
موضوعات مرتبط
علوم زیستی و بیوفناوری
بیوشیمی، ژنتیک و زیست شناسی مولکولی
بیولوژی سلول
پیش نمایش صفحه اول مقاله

چکیده انگلیسی
Mechanical and biochemical alterations were investigated in permeabilized cardiomyocytes along with the progression of dilated cardiomyopathy (DCM) in a transgenic mouse line overexpressing the activated Gαq protein (Tgαq*44). The isometric force, its Ca2+ sensitivity (pCa50) and the turnover rate of the actin-myosin cycle (ktr) were determined at sarcomere lengths (SLs) of 1.9 μm and 2.3 μm before (at 4 and 10 months of age) and after hemodynamic decompensation (at 14 and 18 months of age) in Tgαq*44 cardiomyocytes and in age-matched control cardiomyocytes. The SL-dependence of pCa50 was not different in Tgαq*44 and control hearts. In contrast, a significant increase in pCa50 was observed in the Tgαq*44 cardiomyocytes (ÎpCa50: 0.10-0.15 vs. the controls) after 10 months of age that could be diminished by exposures to the catalytic subunit of protein kinase A (PKA). Accordingly, a decline in endogenous PKA activity and decreased troponin I phosphorylation were detected after 10 months in the Tgαq*44 hearts. Finally, the maximal Ca2+-activated force (Fo) and ktr were lower and the passive force (Fpassive) was higher at 18 months in the Tgαq*44 cardiomyocytes compared to the control. These mechanical alterations were paralleled by a robust increase in β-myosin heavy chain expression in the Tgαq*44 hearts. In conclusion, our data suggested that an initial decrease of PKA signaling and subsequent changes in myofilament protein expression may contribute to the development of dilated cardiomyopathy in Tgαq*44 hearts.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular and Cellular Cardiology - Volume 45, Issue 3, September 2008, Pages 363-372
Journal: Journal of Molecular and Cellular Cardiology - Volume 45, Issue 3, September 2008, Pages 363-372
نویسندگان
István Ferenc Ãdes, Attila Tóth, Gábor Csányi, Magdalena Lomnicka, Stefan ChÅopicki, István Ãdes, Zoltán Papp,