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Ahmad I, Khalid H, Perveen A, Shehroz M, Nishan U, Rahman FU, Sheheryar, Moura AA, Ullah R, Ali EA, Shah M, Ojha SC. Identification of Novel Quinolone and Quinazoline Alkaloids as Phosphodiesterase 10A Inhibitors for Parkinson's Disease through a Computational Approach. ACS OMEGA 2024; 9:16262-16278. [PMID: 38617664 PMCID: PMC11007772 DOI: 10.1021/acsomega.3c10351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/25/2023] [Revised: 03/12/2024] [Accepted: 03/13/2024] [Indexed: 04/16/2024]
Abstract
Phosphodiesterases (PDEs) are vital in signal transduction, specifically by hydrolyzing cAMP and cGMP. Within the PDE family, PDE10A is notable for its prominence in the striatum and its regulatory function over neurotransmitters in medium-spiny neurons. Given the dopamine deficiency in Parkinson's disease (PD) that affects striatal pathways, PDE10A inhibitors could offer therapeutic benefits by modulating D1 and D2 receptor signaling. This study was motivated by the successful history of quinazoline/quinazoline scaffolds in the inhibition of PDE10A. This study involved detailed in silico evaluations through docking followed by pharmacological, pharmacophoric, and pharmacokinetic analyses, prioritizing central nervous system (CNS)-active drug criteria. Seven cyclic peptides, those featuring the quinazoline/quinazoline moiety at both termini, exhibited notably enhanced docking scores compared to those of the remaining alkaloids within the screened library. We identified 7 quinolines and 1 quinazoline including Lepadin G, Aspernigerin, CJ-13536, Aurachin A, 2-Undecyl-4(1H)-quinolone, Huajiaosimuline 3-Prenyl-4-prenyloxyquinolin-2-one, and Isaindigotone that followed the standard CNS active drug criteria. The dominant quinoline ring in our study and its related quinazoline were central to our evaluations; therefore, the pharmacophoric features of these scaffolds were highlighted. The top alkaloids met all CNS-active drug properties; while nonmutagenic and without PAINS alerts, many indicated potential hepatotoxicity. Among the compounds, Huajiaosimuline was particularly significant due to its alignment with lead-likeness and CNS-active criteria. Aspernigerin demonstrated its affinity for numerous dopamine receptors, which signifies its potential to alter dopaminergic neurotransmission that is directly related to PD. Interestingly, the majority of these alkaloids had biological targets primarily associated with G protein-coupled receptors, critical in PD pathophysiology. They exhibit superior excretion parameters and toxicity end-points compared to the standard. Notably, selected alkaloids demonstrated stability in the binding pocket of PDE10A according to the molecular dynamic simulation results. Our findings emphasize the potential of these alkaloids as PDE10A inhibitors. Further experimental studies may be necessary to confirm their actual potency in inhibiting PDE10A before exploring their therapeutic potential in PD.
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Affiliation(s)
- Iqra Ahmad
- Department
of Biochemistry, Bahauddin Zakariya University, Multan 66000, Pakistan
| | - Hira Khalid
- Department
of Biochemistry, Bahauddin Zakariya University, Multan 66000, Pakistan
| | - Asia Perveen
- Department
of Biochemistry, Bahauddin Zakariya University, Multan 66000, Pakistan
| | - Muhammad Shehroz
- Department
of Bioinformatics, Kohsar University Murree, Murree 47150, Pakistan
| | - Umar Nishan
- Department
of Chemistry, Kohat University of Science
& Technology, Kohat 26000, Pakistan
| | - Faiz Ur Rahman
- Department
of Zoology, University of Shangla, Shangla 19100, Khyber Pakhtunkhwa, Pakistan
| | - Sheheryar
- Department
of Animal Science, Federal University of
Ceara, Fortaleza 60020-181, Brazil
| | - Arlindo Alencar Moura
- Department
of Animal Science, Federal University of
Ceara, Fortaleza 60020-181, Brazil
| | - Riaz Ullah
- Department
of Pharmacognosy, College of Pharmacy, King
Saud University, Riyadh 11451, Saudi Arabia
| | - Essam A. Ali
- Department
of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | - Mohibullah Shah
- Department
of Biochemistry, Bahauddin Zakariya University, Multan 66000, Pakistan
| | - Suvash Chandra Ojha
- Department
of Infectious Diseases, the Affiliated Hospital
of Southwest Medical University, Luzhou 646000, China
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Ali Alshehri S, Alsayari A, Wahab S, H Alqarni M, Sweilam SH, Khalid M. Prediction of molecular interaction of Phosphodiesterase 10A inhibition by natural compounds: insights from structure-based screening and molecular dynamics simulations. J Biomol Struct Dyn 2023:1-12. [PMID: 37850684 DOI: 10.1080/07391102.2023.2270756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 10/08/2023] [Indexed: 10/19/2023]
Abstract
Phosphodiesterase 10 A (PDE10A) is an enzyme that regulates cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) levels in the brain, particularly in the striatum, which plays a critical role in movement control and reward processing. Inhibition of PDE10A can increase cAMP and cGMP levels, improving neuronal signaling and reducing symptoms of neuropsychiatric disorders such as schizophrenia, Huntington's disease, and Parkinson's disease. In this study, a structure-based virtual screening was conducted to identify potential anti-neuropsychiatric disorders compounds from phytoconstituents in the IMPPAT database. The ligands were docked against PDE10A, resulting in 40 compounds with appreciable docking scores. These 40 compounds underwent further ADMET predictions and drug likeliness, resulting in five potential compounds. Finally, based on the specific interactions, two compounds (Colladonin and Isopongachromene), were subjected to molecular dynamics (MD) simulation and MM-PBSA studies. The MM-PBSA analysis validated and captured the intermolecular interactions, indicating that Colladonin and Isopongachromene had appreciable binding affinities of -155.60 kJ.mol-1 and -108.28 kJ.mol-1, respectively and were promising candidates against neuropsychiatric disorders, targeting PDE10A. Overall, this study provides insight into the potential of PDE10A inhibitors as therapeutic agents for treating neuropsychiatric disorders, and Colladonin and Isopongachromene are promising compounds for further development.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Saad Ali Alshehri
- Department of Pharmacognosy, College of Pharmacy, King Khalid University, Abha, Saudi Arabia
| | - Abdulrhman Alsayari
- Department of Pharmacognosy, College of Pharmacy, King Khalid University, Abha, Saudi Arabia
| | - Shadma Wahab
- Department of Pharmacognosy, College of Pharmacy, King Khalid University, Abha, Saudi Arabia
| | - Mohammed H Alqarni
- Department of Pharmacognosy, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia
| | - Sherouk Hussein Sweilam
- Department of Pharmacognosy, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia
| | - Mohammad Khalid
- Department of Pharmacognosy, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia
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Ashrafi S, Alam S, Sultana A, Raj A, Emon NU, Richi FT, Sharmin T, Moon M, Park MN, Kim B. Papaverine: A Miraculous Alkaloid from Opium and Its Multimedicinal Application. Molecules 2023; 28:3149. [PMID: 37049912 PMCID: PMC10095881 DOI: 10.3390/molecules28073149] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 03/28/2023] [Accepted: 03/29/2023] [Indexed: 04/05/2023] Open
Abstract
The pharmacological actions of benzylisoquinoline alkaloids are quite substantial, and have recently attracted much attention. One of the principle benzylisoquinoline alkaloids has been found in the unripe seed capsules of Papaver somniferum L. Although it lacks analgesic effects and is unrelated to the compounds in the morphine class, it is a peripheral vasodilator and has a direct effect on vessels. It is reported to inhibit the cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) phosphodiesterase in smooth muscles, and it has been observed to increase intracellular levels of cAMP and cGMP. It induces coronary, cerebral, and pulmonary artery dilatation and helps to lower cerebral vascular resistance and enhance cerebral blood flow. Current pharmacological research has revealed that papaverine demonstrates a variety of biological activities, including activity against erectile dysfunction, postoperative vasospasms, and pulmonary vasoconstriction, as well as antiviral, cardioprotective, anti-inflammatory, anticancer, neuroprotective, and gestational actions. It was recently demonstrated that papaverine has the potential to control SARS-CoV-2 by preventing its cytopathic effect. These experiments were carried out both in vitro and in vivo and require an extensive understanding of the mechanisms of action. With its multiple mechanisms, papaverine can be considered as a natural compound that is used to develop therapeutic drugs. To validate its applications, additional research is required into its precise therapeutic mechanisms as well as its acute and chronic toxicities. Therefore, the goal of this review is to discuss the major studies and reported clinical studies looking into the pharmacological effects of papaverine and the mechanisms of action underneath these effects. Additionally, it is recommended to conduct further research via significant pharmacodynamic and pharmacokinetic studies.
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Affiliation(s)
- Sania Ashrafi
- Department of Pharmaceutical Chemistry, University of Dhaka, Dhaka 1000, Bangladesh
| | - Safaet Alam
- Department of Pharmaceutical Chemistry, University of Dhaka, Dhaka 1000, Bangladesh
- Drugs and Toxins Research Division, BCSIR Laboratories Rajshahi, Bangladesh Council of Scientific and Industrial Research, Rajshahi 6206, Bangladesh
| | - Arifa Sultana
- Department of Pharmaceutical Chemistry, University of Dhaka, Dhaka 1000, Bangladesh
| | - Asef Raj
- Department of Pharmaceutical Chemistry, University of Dhaka, Dhaka 1000, Bangladesh
| | - Nazim Uddin Emon
- Department of Pharmacy, Faculty of Science and Engineering, International Islamic University Chittagong, Chittagong 4318, Bangladesh
- Department of Chemistry and Biochemistry, Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701, USA
| | - Fahmida Tasnim Richi
- Department of Pharmaceutical Chemistry, University of Dhaka, Dhaka 1000, Bangladesh
| | - Tasnuva Sharmin
- Department of Pharmaceutical Chemistry, University of Dhaka, Dhaka 1000, Bangladesh
| | - Myunghan Moon
- Department of Pathology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Moon Nyeo Park
- Department of Pathology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Bonglee Kim
- Department of Pathology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
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Amin HS, Parikh PK, Ghate MD. Medicinal chemistry strategies for the development of phosphodiesterase 10A (PDE10A) inhibitors - An update of recent progress. Eur J Med Chem 2021; 214:113155. [PMID: 33581555 DOI: 10.1016/j.ejmech.2021.113155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 12/27/2020] [Accepted: 01/03/2021] [Indexed: 11/26/2022]
Abstract
Phosphodiesterase 10A is a member of Phosphodiesterase (PDE)-superfamily of the enzyme which is responsible for hydrolysis of cAMP and cGMP to their inactive forms 5'-AMP and 5'-GMP, respectively. PDE10A is highly expressed in the brain, particularly in the putamen and caudate nucleus. PDE10A plays an important role in the regulation of localization, duration, and amplitude of the cyclic nucleotide signalling within the subcellular domain of these regions, and thereby modulation of PDE10A enzyme can give rise to a new therapeutic approach in the treatment of schizophrenia and other neurodegenerative disorders. Limitation of the conventional therapy of schizophrenia forced the pharmaceutical industry to move their efforts to develop a novel treatment approach with reduced side effects. In the past decade, considerable developments have been made in pursuit of PDE10A centric antipsychotic agents by several pharmaceutical industries due to the distribution of PDE10A in the brain and the ability of PDE10A inhibitors to mimic the effect of D2 antagonists and D1 agonists. However, no selective PDE10A inhibitor is currently available in the market for the treatment of schizophrenia. The present compilation concisely describes the role of PDE10A inhibitors in the therapy of neurodegenerative disorders mainly in psychosis, the structure of PDE10A enzyme, key interaction of different PDE10A inhibitors with human PDE10A enzyme and recent medicinal chemistry developments in designing of safe and effective PDE10A inhibitors for the treatment of schizophrenia. The present compilation also provides useful information and future direction to bring further improvements in the discovery of PDE10A inhibitors.
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Affiliation(s)
- Harsh S Amin
- Department of Pharmaceutical Chemistry, Institute of Pharmacy, Nirma University, Ahmedabad, 382 481, Gujarat, India
| | - Palak K Parikh
- Department of Pharmaceutical Chemistry, Institute of Pharmacy, Nirma University, Ahmedabad, 382 481, Gujarat, India; Department of Pharmaceutical Chemistry, L. M. College of Pharmacy, Navrangpura, Ahmedabad, 380 009, Gujarat, India.
| | - Manjunath D Ghate
- Department of Pharmaceutical Chemistry, Institute of Pharmacy, Nirma University, Ahmedabad, 382 481, Gujarat, India
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Czopek A, Partyka A, Bucki A, Pawłowski M, Kołaczkowski M, Siwek A, Głuch-Lutwin M, Koczurkiewicz P, Pękala E, Jaromin A, Tyliszczak B, Wesołowska A, Zagórska A. Impact of N-Alkylamino Substituents on Serotonin Receptor (5-HTR) Affinity and Phosphodiesterase 10A (PDE10A) Inhibition of Isoindole-1,3-dione Derivatives. Molecules 2020; 25:molecules25173868. [PMID: 32854402 PMCID: PMC7504677 DOI: 10.3390/molecules25173868] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 08/22/2020] [Accepted: 08/23/2020] [Indexed: 11/16/2022] Open
Abstract
In this study, a series of compounds derived from 4-methoxy-1H-isoindole-1,3(2H)-dione, potential ligands of phosphodiesterase 10A and serotonin receptors, were investigated as potential antipsychotics. A library of 4-methoxy-1H-isoindole-1,3(2H)-dione derivatives with various amine moieties was synthesized and examined for their phosphodiesterase 10A (PDE10A)-inhibiting properties and their 5-HT1A and 5-HT7 receptor affinities. Based on in vitro studies, the most potent compound, 18 (2-[4-(1H-benzimidazol-2-yl)butyl]-4-methoxy-1H-isoindole-1,3(2H)-dione), was selected and its safety in vitro was evaluated. In order to explain the binding mode of compound 18 in the active site of the PDE10A enzyme and describe the molecular interactions responsible for its inhibition, computer-aided docking studies were performed. The potential antipsychotic properties of compound 18 in a behavioral model of schizophrenia were also investigated.
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Affiliation(s)
- Anna Czopek
- Department of Medicinal Chemistry, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Krakow, Poland; (A.B.); (M.P.); (M.K.); (A.Z.)
- Correspondence: ; Tel.: +48-12-620-5450
| | - Anna Partyka
- Department of Clinical Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Krakow, Poland; (A.P.); (A.W.)
| | - Adam Bucki
- Department of Medicinal Chemistry, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Krakow, Poland; (A.B.); (M.P.); (M.K.); (A.Z.)
| | - Maciej Pawłowski
- Department of Medicinal Chemistry, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Krakow, Poland; (A.B.); (M.P.); (M.K.); (A.Z.)
| | - Marcin Kołaczkowski
- Department of Medicinal Chemistry, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Krakow, Poland; (A.B.); (M.P.); (M.K.); (A.Z.)
| | - Agata Siwek
- Department of Pharmacobiology, Jagiellonian University Collegium Medicum, 9 Medyczna Street, 30-688 Krakow, Poland; (A.S.); (M.G.-L.)
| | - Monika Głuch-Lutwin
- Department of Pharmacobiology, Jagiellonian University Collegium Medicum, 9 Medyczna Street, 30-688 Krakow, Poland; (A.S.); (M.G.-L.)
| | - Paulina Koczurkiewicz
- Department of Pharmaceutical Biochemistry, Jagiellonian University Collegium Medicum, 9 Medyczna Street, 30-688 Krakow, Poland; (P.K.); (E.P.)
| | - Elżbieta Pękala
- Department of Pharmaceutical Biochemistry, Jagiellonian University Collegium Medicum, 9 Medyczna Street, 30-688 Krakow, Poland; (P.K.); (E.P.)
| | - Anna Jaromin
- Department of Lipids and Liposomes, Faculty of Biotechnology, University of Wroclaw, 14a Joliot-Curie, 50-383 Wroclaw, Poland;
| | - Bożena Tyliszczak
- Faculty of Materials Engineering and Physics, Cracow University of Technology, Institute of Materials Science, 24 Warszawska Street, 31-155 Krakow, Poland;
| | - Anna Wesołowska
- Department of Clinical Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Krakow, Poland; (A.P.); (A.W.)
| | - Agnieszka Zagórska
- Department of Medicinal Chemistry, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Krakow, Poland; (A.B.); (M.P.); (M.K.); (A.Z.)
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Itoh K, Ishima T, Kehler J, Hashimoto K. Potentiation of NGF-induced neurite outgrowth in PC12 cells by papaverine: role played by PLC-γ, IP3 receptors. Brain Res 2011; 1377:32-40. [PMID: 21211516 DOI: 10.1016/j.brainres.2010.12.075] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 12/23/2010] [Accepted: 12/23/2010] [Indexed: 10/18/2022]
Abstract
Papaverine, an inhibitor of phosphodiesterase (PDE) 10A, is gaining attention for its potential in the treatment of neuropsychiatric diseases such as schizophrenia. However, the precise mechanisms underlying the putative neuroprotective/neurotrophic actions of papaverine remain unclear. Thus, we investigated the effects of papaverine on nerve growth factor (NGF)-induced neurite outgrowth in PC12 cells. Papaverine potentiated NGF-induced neurite outgrowth in PC12 cells in a concentration-dependent manner. In contrast, the selective PDE10A inhibitor MP-10 had no effect on NGF-induced neurite outgrowth. The potentiation of NGF-induced neurite outgrowth by papaverine was blocked by the PLC-γ inhibitor U73122. Furthermore, papaverine's potentiation of NGF-induced neurite outgrowth was also blocked by the co-administration of inositol 1,4,5-trisphosphate (IP(3)) receptor antagonists (xestospongin C and 2-aminoethoxydiphenyl borate (2-APB)) and by reduced expression of IP(3) receptor gene (i.e., itpr1 and itpr3) by siRNA. Our findings suggest that papaverine could potentiate NGF-induced neurite outgrowth, and that activation of PLC-γ and IP(3) receptors might be involved in the mechanism underlying papaverine's potentiation of neurite outgrowth in PC12 cells.
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Affiliation(s)
- Kanako Itoh
- Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba, Japan
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Sotty F, Montezinho LP, Steiniger-Brach B, Nielsen J. Phosphodiesterase 10A inhibition modulates the sensitivity of the mesolimbic dopaminergic system to D-amphetamine: involvement of the D1-regulated feedback control of midbrain dopamine neurons. J Neurochem 2009; 109:766-75. [PMID: 19236563 DOI: 10.1111/j.1471-4159.2009.06004.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Phosphodiesterase (PDE) 10A is highly expressed in medium spiny neurons of the striatum, at the confluence of the corticostriatal glutamatergic and the midbrain dopaminergic pathways, both believed to be involved in the physiopathology of schizophrenia. There is a growing body of evidence suggesting that targeting PDE10A may be beneficial for the treatment of positive symptoms in schizophrenia. The aim of the present study was to investigate how PDE10A inhibition modulates mesolimbic dopaminergic neurotransmission. We found that the selective PDE10A inhibitor, MP-10, blocked D-amphetamine-induced hyperactivity as well as D-amphetamine-induced dopamine efflux in the nucleus accumbens in a dose-dependent manner. We further investigated the mechanism by which PDE10A inhibition affects dopaminergic neurotransmission. We report that MP-10 potentiated the effect of a high but not a low dose of D-amphetamine on the mean firing rate of dopaminergic neurons recorded from the ventral tegmental area. Similarly, the effect of a high, but not a low dose of D-amphetamine, was completely reversed by the selective D(1) antagonist, SCH23390. These data suggest that the D(1)-regulated feedback control of midbrain dopamine neurons is a critical pathway involved in the modulation of the response of mesolimbic dopamine neurons to D-amphetamine by PDE10A inhibition.
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Affiliation(s)
- Florence Sotty
- Department of Neurophysiology, H. Lundbeck A/S, Copenhagen-Valby, Denmark.
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Siuciak JA, McCarthy SA, Chapin DS, Reed TM, Vorhees CV, Repaske DR. Behavioral and neurochemical characterization of mice deficient in the phosphodiesterase-1B (PDE1B) enzyme. Neuropharmacology 2007; 53:113-24. [PMID: 17559891 DOI: 10.1016/j.neuropharm.2007.04.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2006] [Revised: 04/13/2007] [Accepted: 04/16/2007] [Indexed: 10/23/2022]
Abstract
PDE1B is a calcium-dependent cyclic nucleotide phosphodiesterase that is highly expressed in the striatum. In order to investigate the physiological role of PDE1B in the central nervous system, PDE1B knockout mice (C57BL/6N background) were assessed in behavioral tests and their brains were assayed for monoamine content. In a variety of well-characterized behavioral tasks, including the elevated plus maze (anxiety-like behavior), forced swim test (depression-like behavior), hot plate (nociception) and two cognition models (passive avoidance and acquisition of conditioned avoidance responding), PDE1B knockout mice performed similarly to wild-type mice. PDE1B knockout mice showed increased baseline exploratory activity when compared to wild-type mice. When challenged with amphetamine (AMPH) and methamphetamine (METH), male and female PDE1B knockout mice showed an exaggerated locomotor response. Male PDE1B knockout mice also showed increased locomotor responses to higher doses of phencyclidine (PCP) and MK-801; however, this effect was not consistently observed in female knockout mice. In the striatum, increased dopamine turnover (DOPAC/DA and HVA/DA ratios) was found in both male and female PDE1B knockout mice. Striatal serotonin (5-HT) levels were also decreased in PDE1B knockout mice, although levels of the metabolite, 5HIAA, were unchanged. The present studies demonstrate increased striatal dopamine turnover in PDE1B knockout mice associated with increased baseline motor activity and an exaggerated locomotor response to dopaminergic stimulants such as methamphetamine and amphetamine. These data further support a role for PDE1B in striatal function.
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Affiliation(s)
- J A Siuciak
- CNS Discovery Research, Pfizer Global Research & Development, Pfizer Inc., Eastern Point Road, Groton, CT 06340, USA.
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