Kent Academic Repository Full text document (pdf) Citation for published version Newman-Tancredi, A. (2012) Targeting neurotransmitter receptors for central nervous system therapeutics: from molecular signalling to behavioural pharmacology. Other thesis, University of Kent. DOI Link to record in KAR https://kar.kent.ac.uk/33970/ Document Version Updated Version Copyright & reuse Content in the Kent Academic Repository is made available for research purposes. Unless otherwise stated all content is protected by copyright and in the absence of an open licence (eg Creative Commons), permissions for further reuse of content should be sought from the publisher, author or other copyright holder. Versions of research The version in the Kent Academic Repository may differ from the final published version. Users are advised to check http://kar.kent.ac.uk for the status of the paper. Users should always cite the published version of record. Enquiries For any further enquiries regarding the licence status of this document, please contact: [email protected] If you believe this document infringes copyright then please contact the KAR admin team with the take-down information provided at http://kar.kent.ac.uk/contact.html Targeting neurotransmitter receptors for central nervous system therapeutics: from molecular signalling to behavioural pharmacology A thesis submitted by ADRIAN NEWMAN-TANCREDI B.Sc. (hons); Ph.D. to the UNIVERSITY of KENT for the Degree of DOCTOR OF SCIENCE (D.Sc.) in the Faculty of LIFE SCIENCES 25 June 2012 Since the creation of the world, God’s invisible qualities, his eternal power and divine nature, have been clearly seen, being understood from what has been made. The Bible (Paul’s letter to the Romans ch. 1 verse 20) D.Sc. Thesis Table of Contents Table of Contents Table of Contents .................................................................................................................................... 1 Acknowledgements ................................................................................................................................. 4 Summary ................................................................................................................................................. 5 Candidate Declaration ............................................................................................................................. 6 Publications included in this Thesis ......................................................................................................... 7 Publication metrics ................................................................................................................................ 16 Abbreviations ........................................................................................................................................ 17 Part A: Overview of the publications included in this Thesis ......................................................... 18 1. Introduction ................................................................................................................................... 19 1.1 Key points .............................................................................................................................. 19 1.2 Social burden of psychiatric and neurological disorders ...................................................... 19 Schizophrenia ................................................................................................................................ 20 Depression ..................................................................................................................................... 20 Parkinson’s disease ....................................................................................................................... 21 1.3 Rise of psychopharmacology................................................................................................. 21 Multiple monoamine receptor subtypes ...................................................................................... 22 1.4 Contribution of author’s work .............................................................................................. 22 2. Serotonin 5-HT1A receptor signalling: G-protein activation ......................................................... 25 2.1 Key points .............................................................................................................................. 25 2.2 Background to author’s work ................................................................................................ 25 5-HT1A receptors as targets for CNS disorders .............................................................................. 25 2.3 Contribution of author’s work .............................................................................................. 27 Investigating agonist and inverse agonist influence on ligand binding. ....................................... 27 Investigating agonist and inverse agonist influence on G-protein activation. ............................. 29 Determination of activation at G-protein Gα subunits by antibody capture ............................... 30 Part A: Page 1 of 206 D.Sc. Thesis Table of Contents Gαi3 activation at 5-HT1A receptors: protean agonism and inverse agonism. ............................... 31 2.4 Conclusions and perspectives. .............................................................................................. 32 3. Serotonin 5-HT1A receptor subpopulations and biased agonism .................................................. 34 3.1 Key points .............................................................................................................................. 34 3.2 Background to the author’s work ......................................................................................... 34 Differential functions of pre- and post-synaptic 5-HT1A receptors ............................................... 34 Biased agonism: differential activation of 5-HT1A receptor signaling ........................................... 36 3.3 Contribution of author’s work .............................................................................................. 37 Distinct pharmacological targeting of pre- and post-synaptic 5-HT1A receptors. ......................... 38 Effects of post-synaptic 5-HT1A receptor activation in models of mood and cognition. .............. 40 3.4 Conclusions and perspectives. .............................................................................................. 42 4. Serotonin 5-HT1A receptor activation and psychotic disorders ..................................................... 44 4.1 Key points .............................................................................................................................. 44 4.2 Background to the author’s work ......................................................................................... 44 Serotonin 5-HT1A receptor activation: a mechanism for improved antipsychotic action ............. 45 4.3 Contribution of author’s work .............................................................................................. 47 Binding affinity of recent antipsychotics at D2 and 5-HT1A receptors in vitro ............................... 48 Agonist efficacy of recent antipsychotics at D2 and 5-HT1A receptors in vitro .............................. 49 Activity in rodent models of positive symptoms of schizophrenia ............................................... 50 Activity in rodent models of negative symptoms and cognitive deficits of schizophrenia .......... 52 Activity in models of extrapyramidal symptom liability and side effects ..................................... 54 4.4 Conclusions and perspectives. .............................................................................................. 55 5. Serotonin 5-HT1B and 5-HT1D receptors ......................................................................................... 56 5.1 Key points .............................................................................................................................. 56 5.2 Background to author’s work ................................................................................................ 56 5.3 Contribution of author’s work .............................................................................................. 58 5-HT1B receptors: in vitro constitutive activity and R:G ratios ...................................................... 58 5-HT1B receptors: constitutive activity and “protean” agonism at G-protein subtypes ............... 59 5-HT1D receptors: quantification of its prominent constitutive activity in vitro ........................... 60 Part A: Page 2 of 206 D.Sc. Thesis Table of Contents 5.4 Conclusions and perspectives. .............................................................................................. 62 6. Serotonin 5-HT2A, 5-HT2B and 5-HT2C receptors ............................................................................. 64 6.1 Key points .............................................................................................................................. 64 6.2 Background to the author’s work ......................................................................................... 64 6.3 Contribution of author’s work .............................................................................................. 65 5-HT2A receptors and biased agonism ..........................................................................................