SCS also abolished the response of cardiac DRG neurons to CAO (# P < 0.005 from sham). SCS decreased basal activity of LAD and LCX CAO responsive neurons. In untreated conditions, transient CAO activated cardiac afferent neurons, and that activity remained elevated during the first minute of reperfusion (* P < 0.001 from baseline). B and C: data for individual DRG activity at baseline, CAO, and reperfusion phases in response to left anterior descending (LAD) CAO ( B, n = 37 neurons) and transient (1 min) occlusion of the left circumflex coronary (LCX) artery ( C, n = 44 neurons) without and with preemptive SCS neuromodulation. A: representative response profile of 2 identified ischemic-sensitive DRG soma ( right) without and with preemptive SCS.
![dorsal column stimulator heart dorsal column stimulator heart](https://i0.wp.com/aneskey.com/wp-content/uploads/2019/09/f73-07-9780323401968-1.jpg)
This modulation does not reflect antidromic actions of SCS but likely reflects efferent-mediated changes at the myocyte-sensory neurite interface.Ĭardiac afferent neuron dorsal root ganglion myocardial ischemia spinal cord stimulation sympathetic.Įffects of spinal cord stimulation (SCS) on the evoked response of cardiac-related dorsal root ganglion (DRG) sensory neurons to transient (1 min) coronary artery occlusion (CAO) and into reperfusion. This study determined that thoracic spinal column stimulation (SCS) obtunds the capacity of dorsal root ganglia ventricular afferent neurons to transduce the ischemic myocardium to second-order spinal neurons, a mechanism that would blunt reflex sympathoexcitation to myocardial ischemic stress. NEW & NOTEWORTHY Aberrant afferent signaling drives adverse remodeling of the cardiac nervous system in ischemic heart disease. SCS obtunds the capacity of DRG ventricular neurites to transduce the ischemic myocardium to second-order spinal neurons, a mechanism that would blunt reflex sympathoexcitation to myocardial ischemic stress, thereby contributing to its capacity to cardioprotect. Ventricular fibrillation (VF) was associated with a rapid increase in DRG activity to a maximum of 4.39 ± 1.07 Hz at 20 s after VF induction and a return to 90% of baseline within 10 s thereafter. Suprathreshold SCS (1 Hz) did not activate DRG neurons antidromically ( n = 10 animals).
![dorsal column stimulator heart dorsal column stimulator heart](https://www.mikikomurakami.com/wp-content/uploads/2019/01/Dorsal-root-ganglion-info-web.jpg)
Transient MI was induced by 1-min coronary artery occlusion (CAO) of the left anterior descending (LAD) or circumflex (LCX) artery, randomized as to sequence. In anesthetized canines ( n = 16), extracellular activity generated by 62 dorsal root ganglia (DRG) soma (T1-T3), with verified myocardial ischemic (MI) sensitivity, were evaluated with and without 20-min preemptive SCS (T1-T3 spinal level 50 Hz, 90% motor threshold). The study objective was to determine whether thoracic spinal dorsal column stimulation (SCS) modulates cardiac afferent sensory transduction of the ischemic ventricle. Aberrant afferent signaling drives adverse remodeling of the cardiac nervous system in ischemic heart disease.