Part 1. DOPR Ligands.- 1. Delta Opioid Receptor (DOR) Ligands and Pharmacology: Development of Indolo- and Quinolinomorphinan Derivatives Based on the Message-Address Concept.- 2. Multifunctional Opioid Ligands.- 3. Contribution of Delta-Opioid Receptors to Pathophysiological Events Explored by Endogenous Enkephalins.- Part 2. DOPR Signaling.- 4. Ligand-Directed Signaling at the Delta Opioid Receptor.- 5. Delta Opioid Receptor Expression and Function in Primary Afferent Somatosensory Neurons.- 6. Evidence and Function Relevance of Native DOR–MOR Heteromers.- Part 3. DOPR and Disease.- 8. The Delta Opioid Receptor in Pain Control.- 9. Delta Opioid Receptors and Modulation of Mood and Emotion.- 10. Delta Opioid Pharmacology in Relation to Alcohol Behaviors.- 11. Delta Opioid Receptors: Learning and Motivation.- 12. Delta Opioid Pharmacology in Parkinson’s Disease.- 13. Delta Opioid Receptor and Peptide: A Dynamic Therapy for Stroke and Other Neurological Disorders.- 14. Delta Opioid Receptors and Cardioprotection.- 15. The Roles of Opioid Receptors in Cutaneous Wound Healing.