1) Although exposure to dopamine D2 antagonism results in postsynaptic receptor upregulation and supersensitivity
that underlies the development of dyskinesia, this process is often rapidly reversible in animal models.
Probable mechanism suggested by authors is dopamine supersensitivity
It has new coverage of desensitization and supersensitivity
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psychosis, which is frequently observed together with TD and is considered to have a similar etiology as TD, is a psychotic relapse phenomenon that occurs after the withdrawal of an antipsychotic drug or rapid reduction of the drug dosage (4).
Effects of melatonin on behavioral dopaminergic supersensitivity
In the United States 24% of our population is born with a supersensitivity
The main central mechanisms include (a) the progression of nigrostriatal degeneration, which results in the reduction of the capacity of storing dopamine in the presynaptic vesicles and releasing them physiologically, (b) enhanced conversion of levodopa to dopamine and aberrant release in the striatum as false neurotransmitter by serotoninergic neurons, (c) alterations in dopaminergic receptors that undergo plastic changes, which include supersensitivity
to dopamine because of the loss of nigrostriatal projections, desensitization, and downregulation because of the presence of nonphysiological high doses of dopamine, and (d) increased glutamatergic activity in the striatum [87,88].
However, the Johansen-Juselius test procedure is also not immune to supersensitivity
to the selection of lag-lengths.
and enhanced motivation for reward in mice lacking dopamine D2 autoreceptors.
Migraine is most similar to pure autonomic failure in terms of reduced supine plasma norepinephrine levels, peripheral adrenergic receptor supersensitivity
, and clinical symptomatology directly related to sympathetic nervous system dysfunction.
HET] mice have reduced ACh transmission by central cholinergic neurons (22), compensatory mechanisms, such as supersensitivity
of cholinergic receptors, could account for the normal sleep-wake physiology.
This may reflect heightened sensitivity to the effects of serotonergic dysregulation, and suggests that what underlies impulsive aggression is either supersensitivity
to serotonergic disturbances or susceptibility to fluctuations in central serotonergic availability.