Dopamine receptor in schizophrenia

Wong, D. F. In vivo imaging of D2 dopamine receptors in schizophrenia the ups and downs of neuroimaging research. Arch. Gen. Psychiatr. 59 31-34, 2002. 

Mackay AV, Iversen LL, Rossor M, Spokes E, Bird E, et al. 1982. Increased brain dopamine and dopamine receptors in schizophrenia. Arch Gen Psychiatry 39 991-997. 

Schwartz, J.-C., Diaz, J., Pilon, C., and Sokoloff, P. (2000) Possible implications of the dopamine D3 receptor in schizophrenia and in antipsychotic drug actions. Brain Res Rev 31 277-287. 

There is no evidence for an elevated dopamine content or hypersensitivity of dopamine receptors in the brain of schizophrenic patients. Breakdown products of dopamine and noradrenaline are elevated neither in the urine nor in the blood or cerebrospinal fluid of schizophrenic patients. In some patients with chronic schizophrenia there is even evidence of dopamine hypofunction IKaroum et al.. 1987). 

Wong DF, Wagner HN, Tune LE, et al. Positron emission tomography reveals elevated D-2 dopamine receptors in dmg naive schizophrenia. Science 1986 234 1558-1563. 

Kasper S, Tauscher J, Kufferle B, Bamas C, Pezawas L, Quiner S. Dopamine- and serotonin-receptors in schizophrenia results of imaging-studies and implications for pharmacotherapy in schizophrenia. Eur Arch Psychiatry Clin Neurosci 1999 249(Suppl 4) 83—89. 

Goldman-Rakic PS, Castner SA, Svensoon IH, Siever LJ, Williams GV Targeting the dopamine D1 receptor in schizophrenia insights for cognitive dysfunction. Psychopharmacology 2004 174 3-16. 

Because the evidence for cortical dopamine dysfunction in schizophrenia is indirect, the data can be interpreted in different ways. For example, the increase in DLPFC I) receptors could be seen as a primary phenomenon, and the alteration in WM performance in these patients could result from increased postsynaptic response to DA released in the DLPFC during task performance (Watanabe et al., 1997). According to this alternate hypothesis, WM impairment observed in these patients results from excessive D, receptor transmission (Amsten et al., 1994 Murphy et al., 1996a, b Cai and Arnsten, 1997 ... 

Bai J, He F, Novikova SI, Undie AS, Dracheva S, et al. 2004. Abnormalities in the dopamine system in schizophrenia may lie in altered levels of dopamine receptor-interacting proteins. Biol Psychiatry 56 427-440. 

Okubo Y, Suhara T, Suzuki K, Kobayashi K, Inoue O, et al. 1997. Decreased prefrontal dopamine Dl receptors in schizophrenia revealed by PET. Nature 385 634-636. 

Takahashi H, Higuchi M, Suhara T. 2006. The role of extra-striatal dopamine D2 receptors in schizophrenia. Biol Psychiatry 59 919-928. 

Goldsmith SK, Shapiro RM, Joyce JN. 1997. Disrupted pattern of D2 dopamine receptors in the temporal lobe in schizophrenia. A postmortem study. Arch Gen Psychiatry 54 649-658. 

Murray AM, Hyde TM, Knable MB, Herman MM, Bigelow LB, et al. 1995. Distribution of putative D4 dopamine receptors in postmortem striatum from patients with schizophrenia. J Neurosci 15 2186-2191. 

Two main lines of evidence point to the involvement of dopamine receptors in the etiology of schizophrenia. First, all known antipsychotic medications share the ability to block D2 dopamine receptors (Seeman et al., 1975 Farde et al., 1992 Kasper et al., 1999). Secondly, several studies have reported a subcortical hyperdopaminergic state in schizophrenia indicative of a dysregulation of dopamine in schizophrenia (Laruelle et al., 1999). 

Q10 Haloperidol is an antipsychotic or neuroleptic agent. It is an antagonist at dopamine receptors, particularly of the D2 subtype. These drugs help to control the symptoms (mainly the positive symptoms) of schizophrenia by antagonizing the dopamine receptors in different brain areas, such as the frontal and temporal lobes. Antipsychotic agents, such as haloperidol, take days or weeks to achieve their therapeutic effect and may produce some motor disturbances. 

Impairment of the dopamine system is also implicated in schizophrenia, a mental disease marked by disturbances in thinking and emotional reactions. Drugs, such as chlorpromazine and clozapine, that block dopamine receptors in the brain have been used to alleviate the... 

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