Many Drugs of Abuse May Be Acutely Transformed to Dopamine, Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elev...

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Main Author: Paul J. Fitzgerald
Format: Article
Language:English
Published: MDPI AG 2021-10-01
Series:International Journal of Molecular Sciences
Subjects:
Online Access:https://www.mdpi.com/1422-0067/22/19/10706
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author Paul J. Fitzgerald
author_facet Paul J. Fitzgerald
author_sort Paul J. Fitzgerald
collection DOAJ
description It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.
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spelling doaj.art-81a247f19e454437bb9280f1c07790582023-11-22T16:14:06ZengMDPI AGInternational Journal of Molecular Sciences1661-65961422-00672021-10-0122191070610.3390/ijms221910706Many Drugs of Abuse May Be Acutely Transformed to Dopamine, Norepinephrine and Epinephrine In VivoPaul J. Fitzgerald0Department of Psychiatry, University of Michigan, Ann Arbor, MI 48109, USAIt is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.https://www.mdpi.com/1422-0067/22/19/10706cocaineamphetaminemethamphetamineephedrineMDMAecstasy
spellingShingle Paul J. Fitzgerald
Many Drugs of Abuse May Be Acutely Transformed to Dopamine, Norepinephrine and Epinephrine In Vivo
International Journal of Molecular Sciences
cocaine
amphetamine
methamphetamine
ephedrine
MDMA
ecstasy
title Many Drugs of Abuse May Be Acutely Transformed to Dopamine, Norepinephrine and Epinephrine In Vivo
title_full Many Drugs of Abuse May Be Acutely Transformed to Dopamine, Norepinephrine and Epinephrine In Vivo
title_fullStr Many Drugs of Abuse May Be Acutely Transformed to Dopamine, Norepinephrine and Epinephrine In Vivo
title_full_unstemmed Many Drugs of Abuse May Be Acutely Transformed to Dopamine, Norepinephrine and Epinephrine In Vivo
title_short Many Drugs of Abuse May Be Acutely Transformed to Dopamine, Norepinephrine and Epinephrine In Vivo
title_sort many drugs of abuse may be acutely transformed to dopamine norepinephrine and epinephrine in vivo
topic cocaine
amphetamine
methamphetamine
ephedrine
MDMA
ecstasy
url https://www.mdpi.com/1422-0067/22/19/10706
work_keys_str_mv AT pauljfitzgerald manydrugsofabusemaybeacutelytransformedtodopaminenorepinephrineandepinephrineinvivo