PHYSIOLOGY
CARDIAC MUSCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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increase rate of SA node discharge
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decrease rate of SA node discharge
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decrease excitability of the AV junction fibers
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increase excitability of the AV junction fibers
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Detailed explanation-1: -Typically, vagal stimulation results in sinus node slowing accompanied by slowing of conduction though the AV node.
Detailed explanation-2: -There’s one vagus nerve on each side of your body. The vagus nerve runs from the lower part of the brain through the neck to the chest and stomach. When the vagus nerve is stimulated, electrical impulses travel to areas of the brain. This alters brain activity to treat certain conditions.
Detailed explanation-3: -Atrioventricular Block, Second Degree Caused by high vagal tone: This is a regulatory mechanism at rest whereby a beat-to-beat increase in blood pressure leads to a blocked beat to maintain a stable blood pressure. Drug administration: 2 agonists (detomidine, xylazine) or calcium channel blockers (verapamil).
Detailed explanation-4: -Conclusion: The present experiments suggest that vagal nerve stimulation releases vasoactive intestinal peptide (VIP) or a “VIP-like substance’ that significantly increases right ventricular contraction, relaxation, and heart rate.