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摘要：Although magnetic resonance imaging (MRI) is highly effective in identifying tumor location or size and in detecting even small intracranial lesions, it remains often difficult of differentiating between viable tumor tissue and postsurgical morphological changes such as gliosis or tumor-associated brain edema. PET may help to overcome this dilemma of diagnosis.

de series, is an antipsychotic drug with high selectivity and affinity for central D2-dopamine receptors .

It has been used in research purposes as below:

•Raclopride C 11 is used with positron emission tomography (PET) as a clinical research tool to determine dopamine type 2 (D2) receptor density in the human brain under normal and pathological conditionslike to confirm the age-related decrease in striatal dopamine D2receptor density, which may be associated with a decline in motor as well as cognitive functions.
•It has been used to investigate various disorders involving dopamine deficiency.
•It may be used to examine neuroreceptor distribution and quantities in patients withAlzheimer'sdisease, which may help in the analysis of degenerative alterations of neuron populations and neuroreceptor systems in patients with this disease.本论文由英语论文网整理提供

•It may be useful for investigating the dopaminergic function in the striatum as a means of differentiating patients with multiple system atrophy from patients with Parkinson's disease
•Dopamine D2receptor density assessed in patients withschizophrenia using raclopride C 11 with PET has been used to evaluate the neocortical receptor occupancy of antipsychotic drugs used in the clinical treatment of patients with schizophrenia .

Clinically,

•It may provide a means of detecting subclinical striatal dysfunction, and help in assessing the rate of progression of Huntington's disease.
•In addition, it may be used to evaluate the response to treatment of pituitary tumors, such as prolactinomas, with dopamine agonists (e.g., bromocriptine), and to predict the effect of such treatment.

Source:

Carbon C 11 (11CO2) may be produced by the 11C nuclear reaction on 14N(p,alpha), a target of nitrogen gas.11CO2is used in the preparation of the reactive precursors11C-iodomethane and 1-11C-iodoethane.

Raclopride can be labeled with carbon-11 either byN-ethylation with 1-11C-iodoethane or byO-methylation with11C-iodomethane. Preparations of raclopride C 11 have been shown to be stable at room temperature for 74 minutes.

Dosage (Brain Imaging)

Intravenous, 110 to 496 megabecquerels (3 to 13.4 millicuries), with specific radioactivity between 18.5 and 55.5 megabecquerels (0.5 and 1.5 millicuries), administered as a bolus injection.Striatal uptake and image contrast depend on the mass of raclopride C 11.

At high specific activity, specific binding is much greater than nonspecific uptake, and maximum image contrast between the striatum and cerebellum is obtained. For optimal efficacy in measuring receptor densities, the specific activity of raclopride C 11 should not be less than 18.5 gigabecquerels (500 millicuries) per micromole at the time of calibration.

The radioligand raclopride C 11 is retained in tissue as a result of binding to a neurotransmitter receptor. Raclopride is a selective dopamine antagonist with a high affinity for dopamine type 2 (D2) receptors.Since the neurotransmitter dopamine may be involved in various neuropsychiatric diseases, https://www.51lunwen.org/dxygassignment/ the in vivo binding of raclopride to dopamine receptors in the striatum can be measured by positron emission tomography (PET) with radiolabeled raclopride used as a tracer.

Time to imaging
Immediately after injection, and continued for approximately 60 minu本论文由英语论文网提供整理，提供论文代写，英语论文代写，代写论文，代写英语论文，代写留学生论文，代写英文论文，留学生论文代写相关核心关键词搜索。