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Full-Text Articles in Medical Sciences
Mlck/Actin Interaction In The Contracting A7r5 Cell And Vascular Smooth Muscle, Sean Eric Thatcher
Mlck/Actin Interaction In The Contracting A7r5 Cell And Vascular Smooth Muscle, Sean Eric Thatcher
Theses, Dissertations and Capstones
Myosin light chain kinase (MLCK) is an enzyme that phosphorylates the serine-19 residue on myosin regulatory light chains (MLCs) which serves to activate the Mg2+-ATPase of myosin. This catalytic activity is thought to be the primary role of MLCK; however, it has recently been suggested that MLCK’s actin binding and bundling properties may also be of importance in smooth muscle contraction. In the absence of calcium and calmodulin (CaM), MLCK will bundle actin filaments with its N-terminus. During calcium influx and subsequent CaM activation, MLCK binding to actin decreases resulting in unbundling of actin filaments and allows myosin and actin …
Aging Influences Multiple Indices Of Oxidative Stress In The Heart Of The Fischer 344/Nnia X Brown Norway/Binia Rat, Shinichi Asano
Aging Influences Multiple Indices Of Oxidative Stress In The Heart Of The Fischer 344/Nnia X Brown Norway/Binia Rat, Shinichi Asano
Theses, Dissertations and Capstones
Here we report the influence of aging on multiple markers of oxidativenitrosative stress in the heart of adult (6-month), aged (30-month) and very aged (36- month) Fischer 344/NNiaHSd X Brown Norway/BiNia (F344/NXBN) rats. Compared to 6 month old rat hearts, indices of oxidative (superoxide anion (–O2 ·), 4-hyrdoxy-2- nonenal (4-HNE)) and nitrosative (protein nitrotyrosylation) stress were 34.1 ± 28.1%, 186 ± 28.1% and 94 ± 5.8% higher, respectively, in 36-month hearts and these findings were highly correlated with increases in left ventricular wall thickness (r>0.669; r>0.710 and p<0.01, respectively). Regression analysis showed that increases in cardiac oxidative-nitrosative stress with aging were significantly correlated with changes in the expression and/or regulation of proteins involved in transcriptional (NF-κB) activities, signaling (mitogen activated protein kinases along with Src), apoptotic ( Bcl-2, Traf-2), and cellular stress (HSPs). These results suggest that the aging F344/NXBN heart may be highly suited for unraveling the molecular events that lead to age-associated alterations in cardiac oxidative stress.