How to Induce Arrhythmias with Noradrenaline
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Noradrenaline is a precursor of adrenaline, secreted by the adrenal part of the medulla, and like dopamine is a neurotransmitter found in the brain and other parts of the body. Noradrenaline is important in the response and recovery after injury or serious illness. Furthermore, significant plasma levels are seen in patients with different types of shock, severe hypoxemia, or cardiac failure. Cellular response to noradrenaline is mediated by receptors that are located on target cells. It has the potential of facilitating cardiac arrhythmias by β1 receptor stimulation, alpha-1 receptor stimulation, or increase in myocardial oxygen consumption. When noradrenaline is injected intravenously, a rise in the blood pressure occurs rapidly. The effect is of short duration. After 1–2 min of discontinuation of infusion, the pressor response disappears. Noradrenaline is a sympathicomimetic with a double effect on the α and β postsynaptic receptors. Furthermore, sympathetic stimulation by noradrenaline leads to adrenaline secretion from the medulosuprarenal gland, with further effect on the α and β receptors. On the other hand, the effects of noradrenaline are different of those of adrenaline, even though they both act on the α and β receptors.
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