Brain dopamine D2 receptor

Buspirone has selective anxiolytic effects, and its pharmacologic characteristics are different from those of other drugs described in this chapter. Buspirone relieves anxiety without causing marked sedative, hypnotic, or euphoric effects. Unlike benzodiazepines, the drug has no anticonvulsant or muscle relaxant properties. Buspirone does not interact directly with GABAergic systems. It may exert its anxiolytic effects by acting as a partial agonist at brain 5-HTia receptors, but it also has affinity for brain dopamine D2 receptors. Buspirone-treated patients show no... 

Zhang M, Creese I (1993) Antisense oligodeoxynucleotide reduces brain dopamine D2 receptors behavioral correlates. Neurosci Lett 161 223-226. 

Volkow ND, Wang GJ, Fowler JS, Logan J, Gatley SJ, Gifford A, Hitzemann R, Ding YS, Pappas N (1999c) Prediction of reinforcing responses to psychostimulants in humans by brain dopamine D2 receptor levels. Am J Psychiatry 756 1440—1443. 

The CTZ, located outside the blood-brain barrier (BBB), is exposed to cerebrospinal fluid and blood.2,3 Therefore it is easily stimulated by uremia, acidosis, and the circulation of toxins such as chemotherapeutic agents. The CTZ has many serotonin type 3 (5-HT3), neurokinin-1 (NKj), and dopamine (D2) receptors.2 Visceral vagal nerve fibers are rich in 5-HT3 receptors. They respond to gastrointestinal distention, mucosal irritation, and infection. 

Anokhin, A.P., Torodov, A.A., Madden, P.A.F., Grant, J.D., Heath, A.C. Brain event-related potentials, dopamine D2 receptor gene polymorphism, and smoking. Genet. Epidemiol. 17(Suppl. 1) S37, 1999. 

SpyrakiC., SealfonS. Regulation of dopamine D2 receptor mRNA expression in the olfactory tubercle by cocaine. Mol. Brain Res. 19 313, 1993. 

Eaton WW, Kessler RC, Wittchen ElU, et al Panic disorder and panic in the United States. Am J Psychiatry 151 413-420, 1994 Ebadi MS, Simmons VJ, Hendrickson MJ, et al Pharmacokinetics of lithium and its regional distribution in rat brain. Eur J Pharmacol 27 324-329, 1974 Ebert D, Feistel H, Kaschka W, et al Single photon emission computerised tomography assessment of cerebral dopamine D2 receptor blockade in depression before and after sleep deprivation—preliminary results. Biol Psychiatry 35 880-885, 1994... 

Papp LA, Klein DF, Gorman JM Carbon dioxide hypersensitivity, hyperventilation, and panic disorder. Am J Psychiatry 150 1149-1157, 1993 Papp M, Klimek V, Willner P Parallel changes in dopamine D2 receptor binding in limbic forebrain associated with chronic mild stress-induced anhedonia and its reversal by imipramine. Psychopharmacology 115 441-446, 1994 Parasuraman R, Haxby JV Attention and brain function in Alzheimer s disease. Neuropsychology 7 242-272, 1993... 

Russell RW, Pechnick R, Jope RS Effects of lithium on behavioral reactivity relation to increases in brain cholinergic activity. Psychopharmacology 73 120-125, 1981 Russell VA, Lamm MC, Taljaard JJ Lack of interaction between alpha 2-adrenoceptors and dopamine D2-receptors in mediating their inhibitory effects on [ H] dopamine release from rat nucleus accumbens. Neurochem Res 18 285-289, 1993... 

The "chemoreceptor trigger zone" or area postrema is located at the caudal end of the fourth ventricle. This is outside the blood-brain barrier but is accessible to emetogenic stimuli in the blood or cerebrospinal fluid. The chemoreceptor trigger zone is rich in dopamine D2 receptors and opioid receptors, and possibly serotonin5-HT3 receptors and NKi receptors. 

Jacobson KA, Hoffmann C, Cattabeni F, Abbracchio MP (1999) Adenosine-induced cell death evidence for receptor-mediated signalling. Apoptosis 4(3) 197—211 Kafka SH, Corbett R (1996) Selective adenosine A2A receptor/dopamine D2 receptor interactions in animal models of schizophrenia. Eur J Pharmacol 295(2-3) 147-154 Latini S, Bordoni F, Corradetti R, Pepeu G, Pedata F (1998) Temporal correlation between adenosine outflow and synaptic potential inhibition in rat hippocampal slices during ischemia-like conditions. Brain Res., 794, (2) 325-328. 

Arnsten AF, Cai JX, Steere JC, Goldman-Rakic PS (1995) Dopamine D2 receptor mechanisms contribute to age-related cognitive decline the effects of quinpirole on memory and motor performance in monkeys. J Neurosci 15 3429-39 Arrang JM, Garbarg M, Schwartz JC (1983) Auto-inhibition of brain histamine release mediated by a novel class (H3) of histamine receptor. Nature 302 832-7 Arrang JM, Garbarg M, Schwartz JC (1985) Autoregulation of histamine release in brain by presynaptic H3-receptors. Neuroscience 15 553-62... 

Umemiya M, Berger AJ (1995) Presynaptic inhibition by serotonin of glycinergic inhibitory synaptic currents in the rat brain stem. J Neurophysiol 73 1192-1201 Usiello A, Baik JH, Rouge-Pont F, Picetti R, Dierich A, LeMeur M, Piazza PV, Borrelli E (2000) Distinct functions of the two isoforms of dopamine D2 receptors. Nature 408 199-203 Vanderschuren LJ, Wardeh G, De Vries TJ, Mulder AH, Schoffelmeer AN (1999) Opposing role of dopamine Di and D2 receptors in modulation of rat nucleus accumbens noradrenaline release. J Neurosci 19 4123-31... 

Despite the preponderance of data correlating the dopamine D2 receptor with schizophrenia, alternative sites in the brain (serotonergic, adrenergic, glutamatergic, and GABAergic) are also being investigated to explain the actions of atypical neuroleptics. 

Cross, A. J., Crow, T. J., Owen, E 1981, 3H-Flupenthixol binding in postmortem brains of schizophrenics evidence for a selective increase in dopamine D2 receptors, Psychopharmacology (Berl), vol. 74, no. 2, pp. 122-124. 

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