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PubMed · 10093586

Dopamine agonists.

S A Factor
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Abstract

Dopamine agonists have been used in the treatment of Parkinson's disease (PD) since the mid 1970s. With the approval of two new agents in 1997, the number available in the United States is up to four; bromocriptine, pergolide, pramipexole, ropinirole. These agents differ in dopamine receptor affinities and chemical structure, which, in turn, may possibly result in differences in efficacy tolerability and safety. Dopamine have historically been used in combination with levodopa in patients with advanced PD, but indicators are now expanding. With is expansion comes increasing controversy. This article reviews dopamine receptor pharmacology and the results of the clinical trials that have used for agonists available in the United States as well as a discussion of three minor agonists.

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ApomorphineBenzothiazolesBromocriptineDopamine AgonistsHumansIndolesParkinson DiseasePergolidePramipexoleRandomized Controlled Trials as TopicReceptors, DopamineThiazolesTreatment OutcomeJournal ArticleResearch Support, Non-U.S. Gov'tReview

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S A Factor. 1999. Dopamine agonists.. https://doi.org/10.1016/s0025-7125(05)70112-7

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Apomorphine↗
PubMed2006

Sensitive quantification of apomorphine in human plasma using a LC-ESI-MS-MS method.

An analytical method based on liquid chromatography coupled with ion trap mass spectrometry (MS) detection with electrospray ionization interface has been developed for the identification and quantification of apomorphine in human plasma. Apomorphine was isolated from 0.5 mL of plasma using a liquid-liquid extraction with diethyl ether and boldine as internal standard, with satisfactory extraction recoveries. Analytes were separated on a 5-microm C18 Highpurity (Thermohypersil) column (150 mm x 2.1 mm I.D.) maintained at 30 degrees C, coupled to a precolumn (C18, 5-microm, 10 mm x 2.0 mm I.D., Thermo). The elution was achieved isocratically with a mobile phase of 2 mM NH4COOH buffer pH 3.8/acetonitrile (50/50, vol/vol) at a flow rate of 200 microL per minute. Data were collected either in full-scan MS mode at m/z 150 to 500 or in full-scan tandem mass spectrometry mode, selecting the [M+H]ion at m/z 268.0 for apomorphine and m/z 328.0 for boldine. The most intense daughter ion of apomorphine (m/z 237.1) and boldine (m/z 297.0) were used for quantification. Retention times were 2.03 and 2.11 minutes for boldine and apomorphine, respectively. Calibration curves were linear in the 0.025 to 20 ng/mL range. The limits of detection and quantification were 0.010 ng/mL and 0.025 ng/mL, respectively. Accuracy and precision of the assay were measured by analyzing 54 quality control samples for 3 days. At concentrations of 0.075, 1.5, and 15 ng/mL, intraday precisions were less than 10.1%, 5.3%, and 3.8%, and interday precisions were less than 4.8%, 6.6%, and 6.5%, respectively. Accuracies were in the 99.5 to 104.2% range. An example of a patient who was given 6 mg of apomorphine subcutaneously is shown, with concentrations of 14.1 ng/mL after 30 minutes and 0.20 ng/mL after 6 hours. The method described enables the unambiguous identification and quantification of apomorphine with very good sensitivity using only 0.5 mL of sample, and is very convenient for therapeutic drug monitoring and pharmacokinetic studies.

Apomorphine↗