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New treatment for erectile dysfunction.

R T Segraves
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Abstract

Numerous advances have been made in our understanding of the evaluation and treatment of erectile dysfunction. Numerous treatment options are currently available. Treatment of this disorder was revolutionized by the introduction of sildenafil, an oral vasoactive agent that has a peripheral mechanism of action, blocking the degradation of cyclic guanosine monophosphate, and thus augmenting the erectogenic effect of sexual stimulation. This agent has proven efficacy in a variety of patient populations, including psychiatric patients. Clinical series suggest that this agent will reverse erectile dysfunction induced by psychoactive agents. Thus, it may play a role in decreasing treatment noncompliance associated with drug-induced sexual dysfunction. Another novel agent that is in development may be of special interest to psychiatrists. Apomorphine is a central dopamine agonist that is believed to act at the level of the paraventricular nucleus of the hypothalamus. As new agents are evolving, our understanding of the neurobiology of sexual function is advancing.

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ApomorphineClinical Trials as TopicDopamine AgonistsErectile DysfunctionHumansMalePhosphodiesterase InhibitorsPiperazinesPurinesSildenafil CitrateSulfonesVasodilator AgentsJournal ArticleReview

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BibTeXRIS

R T Segraves. 2000. New treatment for erectile dysfunction.. https://doi.org/10.1007/s11920-996-0009-z

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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↗