The first action potential is produced by a small group of specialized cardiac cells, called the pacemaker cells, which are located in the border zone between the sinus venosus and the atrium. Because all cardiac muscle cells are electrically connected, this action potential can rapidly spread ...
Action potentialCardiac conductionElectroencephalogramThe propagation of the action potential in contractile artrial and ventricular fibres is explained by this simulated electronic circuit which has a one-to-one correspondence for its elements with the major constituents of the cardiac fibres. The ...
Upregulation of Ndufs1 expression alleviated this damage, which could be explained by improved complex I activity. Increased ROS generation can promote apoptosis through multiple pathways36,37. This study focused on direct damage to DNA in the nucleus due to elevated ROS levels and the activation ...
This difference can be explained by the prolonged seated position during the protocol, as well as by a higher level of stress in the first session, owing to the unusual experimental situation for participants. This reduction of about 10 bpm was enough to increase overall HRV, as this measure ...
There is a large variation in survival between communities that is not explained by patient or community factors. Study of variation in outcome in other related conditions suggest that this is due to differences in organizational culture rather than processes of care. A public health approach to ...
Moreover, the effect of testosterone on IK1 was evident only in the outward component of the current, an observation that also cannot readily be explained by a change in the expression of the K+ channel α-subunit itself (Liu et al., 2003b). Further evidence for a protective action of ...
The discrepancy between such views and the consistently opposite evidence derived from in vivo animal experiments can be explained on the basis of a misconception of the mechanism of action. In arterial stenoses, platelets are activated by increased platelet shear stress caused by the narrowing of ...
It has been well documented that the size of the Ca2+transients in ventricular myocytes is directly proportional to the magnitude of the L-type Ca2+current [6]. To determine whether smaller Ca2+transients in females could be explained by a decrease in Ca2+current density, Ca2+currents have be...
Abstract Of the ions involved in the intricate workings of the heart, calcium is considered perhaps the most important. It is crucial to the very process that enables the chambers of the heart to contract and relax, a process called excitation–contraction coupling. It is important to understand...
Importantly, these prior studies have not explained how doses in the range of 25 Gy can reduce VT burden acutely. The presence of structural or electrical heterogeneity in the heart increases the probability of unidirectional block and reentrant tachycardia23,24. For sustained reentry, the ...