Denervation supersensitivity is the sharp increase of sensitivity of post-synaptic membranes to a chemical transmitter after denervation. It is a compensatory change.
MECHANISM: Cause of denervative supersentivity is unknown part of answer is that the number of receptors in the post synaptic membrane of effector cells increases when norepinephrine or acetylcholine is no longer released at synapse, a process called upregulation of receptor. Therefore when a dose of hormone is now injected into the circulatory blood, the effector reaction is vastly enhanced.
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