David E Nichols

David E Nichols
Purdue University West Lafayette | Purdue · Department of Medicinal Chemistry and Molecular Pharmacology (MCMP)

PhD

About

380
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Publications

Publications (380)
Article
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This brief review highlights some of the structure–activity relationships of classic serotonergic psychedelics. In particular, we discuss structural features of three chemotypes: phenethylamines, ergolines and certain tryptamines, which possess psychedelic activity in humans. Where they are known, we point out the underlying molecular mechanisms ut...
Article
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The κ-opioid receptor (KOR) represents a highly desirable therapeutic target for treating not only pain but also addiction and affective disorders¹. However, the development of KOR analgesics has been hindered by the associated hallucinogenic side effects². The initiation of KOR signalling requires the Gi/o-family proteins including the conventiona...
Article
Serotonin (5-hydroxytryptamine [5-HT]) 5-HT2-family receptors represent essential targets for lysergic acid diethylamide (LSD) and all other psychedelic drugs. Although the primary psychedelic drug effects are mediated by the 5-HT2A serotonin receptor (HTR2A), the 5-HT2B serotonin receptor (HTR2B) has been used as a model receptor to study the acti...
Article
Full-text available
Psychedelics are a relatively recent field of research that had not gained much support half a century ago, yet it developed into a much acknowledged, highly relevant field that extends to many people's lives. Psychedelics have demonstrated profound and durable therapeutic potential for the treatment of several psychiatric disorders including depre...
Article
Full-text available at Cell Sneak Peak: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4072041
Article
Hallucinogens like lysergic acid diethylamide (LSD), psilocybin, and substituted N-benzyl phenylalkylamines are widely used recreationally with psilocybin being considered as a therapeutic for many neuropsychiatric disorders including depression, anxiety, and substance abuse. How psychedelics mediate their actions-both therapeutic and hallucinogeni...
Article
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Background In the past few years, the issue of ‘microdosing’ psychedelics has been openly discussed in the public arena where claims have been made about their positive effect on mood state and cognitive processes such as concentration. However, there are very few scientific studies that have specifically addressed this issue, and there is no agree...
Article
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Rationale The lysergamide lysergic acid diethylamide (LSD) is a prototypical classical hallucinogen with remarkably high potency. LSD remains a popular recreational drug but is also becoming an important research tool for medical and neuroscience studies. Recently, several lysergamides that are close structural analogs of LSD have been sold as recr...
Article
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The author of this article wanted to change the Acknowledgments section to: These studies were supported by an award from NIDA (R01 DA041336), as well as by the Veteran’s AdministrationVISN 22 Mental Illness Research, Education, and Clinical Center. Receptor binding and functional data were generously provided by the National Institute of Mental He...
Article
Hallucinogenic drugs potently alter human behavior and have a millennia-long history of use for medicinal and religious purposes. Interest is rapidly growing in their potential as CNS modulators and therapeutic agents for brain conditions. Anti-muscarinic cholinergic drugs, such as atropine and scopolamine, induce characteristic hyperactivity and d...
Article
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The vibrational theory of olfaction is an attempt to describe a possible mechanism for olfaction which is explanatory and provides researchers with a set of principles which permit predictions allowing for structure-odor relations. Similar theories have occurred several times throughout olfactory science; this theory has again recently come to prom...
Article
Psychedelic drugs, such as lysergic acid diethylamide (LSD), mescaline, and psilocybin, exert profound effects on brain and behavior. After decades of difficulties in studying these compounds, psychedelics are again being tested as potential treatments for intractable biomedical disorders. Preclinical research of psychedelics complements human neur...
Article
Full-text available
Lysergic acid diethylamide (LSD) is perhaps one of the best-known psychoactive substances and many structural modifications of this prototypical lysergamide have been investigated. Several lysergamides were recently encountered as "research chemicals" or new psychoactive substances (NPS). Although lysergic acid morpholide (LSM-775) appeared on the...
Article
Full-text available
Significance Herein, we test the present iteration of the vibrational theory of protein activation by comparing predictions obtained from Turin’s vibrational theory for the activation of olfactory receptors measuring affinity and activation at a nonolfactory receptor family of G protein-coupled receptors. This was done at the CNS serotonin receptor...
Article
The prototypical hallucinogen LSD acts via serotonin receptors, and here we describe the crystal structure of LSD in complex with the human serotonin receptor 5-HT2B. The complex reveals conformational rearrangements to accommodate LSD, providing a structural explanation for the conformational selectivity of LSD’s key diethylamide moiety. LSD disso...
Article
Scientific interest in serotonergic psychedelics (e.g., psilocybin and LSD; 5-HT2A receptor agonists) has dramatically increased within the last decade. Clinical studies administering psychedelics with psychotherapy have shown preliminary evidence of robust efficacy in treating anxiety and depression, as well as addiction to tobacco and alcohol. Mo...
Article
Chronic administration of lysergic acid diethylamide (LSD) every other day to rats results in a variety of abnormal behaviors. These build over the 90 day course of treatment and can persist at full strength for at least several months after cessation of treatment. The behaviors are consistent with those observed in animal models of schizophrenia a...
Article
This essay describes the founding of the Heffter Research Institute in 1993 and its development up to the present. The Institute is the only scientific research organization dedicated to scientific research into the medical value of psychedelics, and it has particularly focused on the use of psilocybin. The first clinical treatment study was of the...
Article
Full-text available
Many psychoactive drugs are used recreationally, particularly by young people. This use and its perceived dangers have led to many different classes of drugs being banned under national laws and international conventions. Indeed, the possession of cannabis, 3,4-methylenedioxy-N-methylamphetamine (MDMA; also known as ecstasy) and psychedelics is str...
Article
Based on the structure of the superpotent 5-HT(2A) agonist 2-(4-bromo-2,5-dimethoxyphenyl)-N-[(2-methoxyphenyl)methyl]ethanamine, which consists of a ring-substituted phenethylamine skeleton modified with an N-benzyl group, we designed and synthesized a small library of constrained analogues to identify the optimal arrangement of the pharmacophoric...
Article
Full-text available
A strategy to replace the ethylamine side chain of 2,5-dimethoxy-4-iodoamphetamine (DOI, 1a), and 2,5-dimethoxy-4-bromoamphetamine (DOB, 1b) with a cyclopropylamine moiety was successful in leading to compounds with high affinity at the 5-HT(2) family of receptors; and the more potent stereoisomer of the cyclopropane analogues had the expected (-)-...
Article
This work describes the identification of a novel class of octahydrobenzo[f]quinolines as dopamine D(3)-selective full agonists. We developed a facile method that utilizes Suzuki coupling for easy incorporations of various substituted pendant rings into the scaffold. A small focused library of octahydrobenzo[f]quinolines 5 was synthesized, and thes...
Article
Of the 14 known types of serotonin receptors one of the most extensively studied is the 5-HT2A (5-hydroxytryptamine) receptor. In the brain, this receptor plays a key role in regulation of cortical function and cognition, appears to be the principal target for the hallucinogenic/psychedelic drugs such as lysergic acid diethylamide (LSD), and also i...
Article
The objective of this work is to characterize genetic and proteomic changes in a novel rat model of schizophrenia. Three‐month treatment with low doses of the hallucinogenic drug, LSD, induces a range of abnormal behaviors including social deficits, hyperactivity, and anhedonia. These behavioral changes persist in the absence of drug , and likely r...
Article
Full-text available
To refine further the structure-activity relationships of D(1) dopamine receptor agonists, we investigated the roles of three conserved serine residues [Ser198(5.42), Ser199(5.43), and Ser202(5.46)] in agonist binding and receptor activation. These transmembrane domain 5 (TM5) residues are believed to engage catechol ligands through polar interacti...
Article
Ayahuasca is a psychoactive tea prepared from a combination of plants that contain a hallucinogenic tryptamine and monoamine oxidase inhibitors (MAOIs). Behavioral pattern monitor (BPM) experiments demonstrated that the combination of 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) and a behaviorally inactive dose of an MAO(A) inhibitor such as harmal...
Article
Preclinical evidence indicates that D₁ dopamine receptor full agonists have potential as therapeutic agents for a variety of neurological conditions. Dihydrexidine (DHX) was the first high potency selective D₁ dopamine receptor full agonist and has been studied as a possible treatment for Parkinson's disease (PD). Recently, we discovered doxanthrin...
Article
The treatment of ethyl 6-formyl-5-(1H-indol-4-yl)pyridine-3-carboxylate (2) with NaOMe or NaOH in methanol solution at room temperature under the reported reaction conditions afforded solely product 4 in 80% yield, rather than anticipated product 3.
Article
Efforts to develop selective agonists for dopamine D(1)-like receptors led to the discovery of dihydrexidine and doxanthrine, two bioisosteric β-phenyldopamine-type full agonist ligands that display selectivity and potency at D(1)-like receptors. We report herein an improved methodology for the synthesis of substituted chromanoisoquinolines (doxant...
Article
Activation of the dopaminergic system underlies the behavioral effects of (+)-amphetamine, and plays a major role in its discriminative stimulus properties. Although serotonin receptors modulate dopamine levels in the brain, and 5-HT(1A) and 5-HT(2) receptor agonists do not mimic (+)-amphetamine, pretreatment with 5-HT(2A/2C) agonists significantly...
Article
To assess the effect of conformational mobility on receptor activity, the β-phenyl substituent of dopamine D(1) agonist ligands of the phenylbenzazepine class, (±)-6,6a,7,8,9,13b-hexahydro-5H-benzo[d]naphtho[2,1-b]azepine-11,12-diol (8), and its oxygen and sulfur bioisosteres 9 and 10, respectively, were synthesized as conformationally-restricted a...
Article
This study was designed to determine whether a 5-HT(2C) receptor antagonist could induce a conditioned place preference indicative of reward and/or abuse potential. Here, we present the first evidence that a selective 5-HT(2C) receptor antagonist, 6-chloro-5-ethoxy-N-(pyridin-2-yl)indoline-1-carboxamide hydrochloride (CEPC), can potentiate a low do...
Article
To probe the space at the floor of the orthosteric ligand binding site in the dopamine D(1) receptor, four methylated analogues of dihydrexidine (DHX) were synthesized with substitutions at the 7 and 8 positions. The 8α-axial, 8β-equatorial, and 7α-equatorial were synthesized by photochemical cyclization of appropriately substituted N-benzoyl enami...
Article
Full-text available
A novel class of isochroman dopamine analogues, originally reported by Abbott Laboratories, have >100-fold selectivity for D₁-like over D₂-like receptors. We synthesized a parallel series of chroman compounds and showed that repositioning the oxygen atom in the heterocyclic ring decreases potency and confers D₂-like receptor selectivity to these co...
Article
The phenoxypropylamine derivative tomoxetine has been shown to inhibit noradrenaline (NA) uptake into synaptosomes from rat hypothalamus (Wong et al 1982). Differences in the potencies of the resolved optical isomers, (-)-tomoxetine (I) and (+)-tomoxetine were also noted, the (-)-isomer being more potent than the racemate or the (+)-isomer in-vitro...
Article
Many people who take LSD experience a second temporal phase of LSD intoxication that is qualitatively different, and was described by Daniel Freedman as "clearly a paranoid state." We have previously shown that the discriminative stimulus effects of LSD in rats also occur in two temporal phases, with initial effects mediated by activation of 5-HT(2...
Article
Full-text available
To assess the importance of conformation and placement of the β-substituent of agonist ligands targeted to the D 1 dopamine receptor, (±)-trans-6,6a,7,8,13,13a-hexahydrobenzo[e]chromeno [3,4-b]azepine-2,3-diol 5 and (±)-trans-6,6a,7,8,9,13b-hexahydrobenzo[d]chromeno[3,4-b]azepine-2,3-diol 6 were synthesized as ring-expanded analogues of the high af...
Article
The isolation of diastereomerically pure cis‐2,4‐pentanediol from a crude mixture of both cis‐ and trans‐2,4‐pentanediols is described through a short procedure involving thermodynamic acetal formation with acetophenone, followed by hydrogenolysis of the acetal protecting group.
Article
Hallucinogens are a class of substances that induce profound changes in perception and cognition. A closely related drug, 3,4-methylenedioxymethamphetamine (MDMA), produces euphoria and a feeling of empathy, with minimal sensory distortion. Both of these classes of substances produce their effects by interacting with the serotonergic system. This c...
Article
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Article
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Article
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Article
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Article
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Article
The octahydrobenzo[h]isoquinoline scaffold is of interest as a conformationally-restricted phenethylamine that may be useful for constructing biologically active products. Surprisingly, however, no tractable synthesis of this ring system has been reported. We now describe a facile method for obtaining this framework, and illustrate that our approac...
Article
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Article
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Article
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Article
Full-text available
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Article
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Article
Two 2,3-dihydrobenzofuran analogues of hallucinogenic amphetamines were prepared and evaluated for activity in the two-lever drug-discrimination paradigm in rats trained to discriminate saline from LSD tartrate (0.08 mg/kg) and for the ability to displace [125I]-(R)-DOI [( 125I]-(R)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane) from rat cortical h...
Article
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Article
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Article
In this study, we employed site‐directed mutagenesis to explore the complex hydrogen bonding interactions that are critical for D1 dopamine receptor activation. We stably expressed wild‐type and three transmembrane 5 serine to alanine mutants (S198(5.42)A, S199(5.43)A, and S202(5.46)A) in HEK 293 cells, and evaluated binding affinity and potency of...
Article
Benzofuran, indan and tetrahydronaphthalene analogs of 3,4-(methylenedioxy)amphetamine (MDA) were prepared in order to examine the role of the dioxole ring oxygen atoms of MDA in interacting with the serotonin and catecholamine uptake carriers. The series of compounds was evaluated for discriminative stimulus effects in rats trained to discriminate...
Article
The cyclic ketone, 6,7-dimethoxy-2-tetralone, a versatile starting material for many dopaminergic compounds, can be prepared practically, cost- effectively and in good overall yield. The synthesis starts from readily available 3,4-dimethoxyphenylacetic acid. Ring iodination gave the 2-iodo- 4,5-dimethoxy acid, which was converted to its methyl este...
Article
Full-text available
Neurotransmitter transporters are responsible for removal of biogenic amine neurotransmitters after release into the synapse. These transporters are the targets for many clinically relevant drugs, such as antidepressants and psychostimulants. A high resolution crystal structure for the monoamine transporters has yet to be solved. We have developed...
Article
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Article
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Article
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Chapter
A survey is presented of the development of dopamine D1 receptor-selective drugs, including agonists and antagonists. It is noted that there are presently no ligands that are specific for the D1 vs the D5 receptor isoforms. A general discussion is presented on the structure–activity features of D1/D5 selective agents, with the conclusions developed...
Article
magnified image A series of novel ligands for the serotonin 5‐HT 2A/C receptor subtype bearing the 2‐phenylethylamine pharmacophore was synthesized and assayed for its 5‐HT 2A receptor binding affinity. As the 4′‐aryl‐substituted 2‐(2,5‐dimethoxyphenyl)ethylamines were previously unknown, an initial series of twelve compounds was chosen to obtain i...
Article
An attempt was made to study the steric effects in charge-transfer complexes by selecting two enantiomers, (R) and (S) 2-(2-butyl)anisole, as models of electron donors. A phenyl ring was placed parallel and adjacent to one face of each of the enantiomers, and the conformational properties of the 2-butyl groups were studied. Calculations of conforma...
Article
A new model is proposed for the calculation of the solvation effect for hydrogen-bonded ionic species. The model is applied to a group of phenethylamine and amphetamine derivatives possessing a cationic ammonium group. This N+H3 moiety is common among many compounds of biological interest. A detailed description of the solvation model is presented....
Article
In-vitro studies have shown that WAY 100635 is not only a potent 5-HT1A antagonist, but also has high affinity and efficacy at the dopamine D(4) receptor. Nevertheless, the behavioral effects of this compound have not been investigated. This study sought to characterize the discriminative stimulus effects produced by WAY 100635. Male Sprague-Dawley...
Article
An efficient synthesis of the dopamine D(1) selective full agonist dihydrexidine has been achieved in high yields and requiring no chromatographic separations via a facilitated intramolecular Henry cyclization of a (nitropropyl)benzophenone and subsequent diastereomerically selective reduction of the resulting tricyclic nitroalkene.
Article
Parkinson's disease is a neurodegenerative condition involving the death of dopaminergic neurons in the substantia nigra. Dopamine D(1) receptor agonists are potential alternative treatments to current therapies that employ L-DOPA, a dopamine precursor. We evaluated the pharmacological profiles of the enantiomers of a novel dopamine D(1) receptor f...
Article
This experiment presents a guided-inquiry approach to the demonstration of diastereoselectivity in an undergraduate organic chemistry laboratory. Chiral hindered ketones such as estrone, undergo facile reduction with sodium borohydride in a highly diastereoselective manner. The diastereomeric estradiols produced in the reaction can be analyzed and...
Article
The sodium-dependent transporters for dopamine, norepinephrine, and serotonin that regulate neurotransmission, also translocate the neurotoxin 1-methyl-4-phenylpyridinium (MPP(+)). Previous studies implicated residues in transmembrane helix (TMH) XI of DAT as important sites for MPP(+) transport. We examined the importance of TMH XI residues F551 a...
Article
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Article
Full-text available
Lysergic acid diethylamide (LSD) differs from other types of hallucinogens in that it possesses direct dopaminergic effects. The exact nature of this component has not been elucidated. The present study sought to characterize the effects of several dopamine D(4) agonists and antagonists on the discriminative stimulus effect of LSD at two pretreatme...
Article
The title compound ([3H]INBMeO) was prepared by an O,O-dimethylation reaction of a t-BOC protected diphenolic precursor using no carrier added tritiated iodomethane in DMF with K(2)CO(3). Removal of the t-BOC protecting group and purification by HPLC afforded an overall yield of 43%, with a radiochemical purity of 99% and specific activity of 164Ci...
Article
Phenylalkylamines that possess conformationally rigidified furanyl moieties in place of alkoxy arene ring substituents have been shown previously to possess the highest affinities and agonist functional potencies at the serotonin 5-HT(2A) receptor among this chemical class. Further, affinity declines when both furanyl rings are expanded to the larg...
Article
Full-text available
The human serotonin transporter (hSERT) regulates the spatial and temporal actions of serotonin (5-HT) neurotransmission by removing 5-HT from the synapse. Previous studies have identified residues in the third transmembrane helix (TMH) that may be important for substrate translocation or antagonist recognition. We identified hSERT residues in TMH...
Article
Serotonin is under the class of monoamine neurontransmitters which all of them have a chemical template composed of a basic amino group that are separated by a two carbon aliphatic chain from an aromatic nucleus. Serotonin belongs to one of the most ancient signaling molecules that is found in the single-celled eukaryotes paramecium and tetrahymena...
Article
The lipophilicity of a set of 5-HT(2A) ligands was determined using immobilized-artificial-membrane chromatography, a method that generates values well correlated with octanol-water partition coefficients. For agonists, a highly significant linear correlation was observed between binding affinity and lipophilicity. For ligands exhibiting partial ag...
Article
Appropriate removal of monoamine neurotransmitters after release into the synapse is mediated by presynaptic transporters. Many neurological disorders have been implicated in the dysfunction of these important drug targets. A high‐resolution crystal structure for the monoamine transporters is yet to be resolved. We have developed a homology model f...
Article
In 1991, DeNinno and colleagues described a novel class of isochroman dopamine analogues. Many of these ligands possessed greater than 100‐fold selectivity for dopamine D1 vs. D2 receptors. We studied a parallel series of chroman compounds. Surprisingly, we demonstrated that repositioning the oxygen atom in the heterocyclic ring conferred D2 recept...
Article
We assessed the relative importance of two serine residues located near the top of transmembrane helix 5 of the human 5-HT(2A) receptor, comparing the wild type with S5.43(239)A or S5.46(242)A mutations. Using the ergoline lysergic acid diethylamide (LSD), and a series of substituted tryptamine and phenethylamine 5-HT(2A) receptor agonists, we foun...
Article
Full-text available
Changes in ambient temperature are known to alter both the hyperthermic and the serotonergic consequences of 3,4-methylenedioxymethamphetamine (MDMA). Metabolism of MDMA has been suggested to be a requisite for these neurotoxic effects, whereas the hyperthermic response is an important contributing variable. The aim of the present study was to inve...
Article
Activation of 5-HT(2A) receptors is thought to mediate the hallucinogenic effects of LSD. Nevertheless, in a previous report we provided evidence that a delayed temporal phase of the behavioral pharmacology of LSD is mediated by D(2)-like dopamine receptor stimulation. In this study rats were trained to discriminate LSD with either a 30 min preinje...
Article
Full-text available
Dopamine D1 receptors play an important role in memory and cognition in non-human primates. Dopamine D1 agonists have been shown to reverse performance deficits in both aged non-human primates and in primates with lesions to dopamine systems. This study explored whether a single dose of the first full D1 agonist dihydrexidine (DAR-0100) would cause...
Article
The potential of dopamine D(1) receptor agonists to have beneficial effects on cognitive function has been suggested by a body of preclinical evidence. We now report the use of dihydrexidine (DAR-0100), the first full D(1) agonist, in a pilot study assessing single low dose safety and tolerability in patients with schizophrenia. A within-subject cr...
Article
The recreational drug 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) increases locomotor activity when administered to rats. Although the published pharmacology of MDMA has focused almost exclusively on the roles of serotonin and dopamine, in vitro studies indicate that MDMA induces serotonin and norepinephrine release with equal potency. The pr...
Article
A novel substituted cysteine accessibility method (SCAM) reagent was developed for monoamine uptake transporters. The new reagent, MTS-MPP(+), was a derivative of the neurotoxin and transporter substrate MPP(+). MTS-MPP(+) labeled cysteine residues introduced into the serotonin transporter protein. Although it did not prove to be a substrate, as is...
Article
Full-text available
The concept of intrinsic efficacy has been enshrined in pharmacology for half of a century, yet recent data have revealed that many ligands can differentially activate signaling pathways mediated via a single G protein-coupled receptor in a manner that challenges the traditional definition of intrinsic efficacy. Some terms for this phenomenon inclu...