1st Edition
Basic Pharmacology Understanding Drug Actions and Reactions
Intended for use in an introductory pharmacology course, Basic Pharmacology: Understanding Drug Actions and Reactions provides an in-depth discussion of how to apply the chemical and molecular pharmacology concepts, a discussion students need for more advanced study. The textbook introduces the principles of chemistry and biology necessary to understand drug interactions at the cellular level. The authors highlight chemical and physical properties of drugs, drug absorption and distribution, drug interactions with cellular receptors, and drug metabolism and elimination.
The book begins with a review of chemical principles as they apply to drug molecules, focusing mainly on those for commonly prescribed drugs. The authors use drug structures to illustrate the chemical concepts learned in general and organic chemistry courses. They cover the dynamics of receptors in mediating the pharmacological effects of drugs. They clarify theories, drawn from the scientific literature, which explain drug-receptor interactions and the quantitative relationship between drug binding and its effects at the cellular level.
The authors’ extensive use of drug structures for teaching chemical and molecular pharmacology principles, and their emphasis on the relevance of these principles in future professional life makes this book unique. It provides the framework for better understanding of advanced pharmacology and therapeutics topics. Blending medicinal chemistry and pharmacodynamics aspects, this textbook clearly elucidates the essential concepts that form the cornerstone for further work in pharmacology.
PHYSICOCHEMICAL PROPERTIES OF DRUGS
Basic Chemical Properties of Drugs
Introduction
The Periodic Table and Properties of Drugs
The Periodic Table and Chemical Reactivity
Chemical Bonds
Magnitude of Ionic Charge
Polyatomic Ions
Covalent Bonds
Coordinate Covalent Bonds
Resonance Structures
Shapes of Drug Molecules
Electronegativity
Polarity of Chemical Bonds
Molecular Polarity
Further Reading
Acid–Base Properties of Drugs
Hydrolysis of Salts
Conjugate Acids and Conjugate Bases
Strength of Acids and Bases
Resonance and Inductive Effects
Inductive Effects
Resonance Effects
The Henderson–Hasselbach Equation
Further Reading
Structural Determinants of Drug Action
Structurally Nonspecific Drugs
Volatile Anesthetics
Structurally Specific Drugs
Isosterism and Isosteres
Structural Changes in Drug Molecules
Further Reading
Chemical Approaches to the Treatment of Cancer
Normal vs. Malignant Cells
Cell Cycle and Chemotherapy
From Chemical Warfare to Chemotherapy
Anticancer Drugs
Further Reading
PRINCIPLES OF BIOPHARMACEUTICS
Administration and Absorption of Drugs
Drug Administration
Drug Absorption
Physiological and Physicochemical Factors in Drug Absorption
Drug Absorption, Bioavailability, and First-Pass Metabolism
Further Reading
Distribution and Excretion of Drugs
Factors in Drug Distribution
Patterns of Distribution
Determination of the Volume of Distribution
Clearance and Elimination Rate
Clearance and the Maintenance Dose Rate
Half-Life and the Steady State
Bioavailability
Drug Elimination
Further Reading
Metabolic Changes of Drugs
Cytochromes P450
Redox Reactions and the CYP450 Enzyme Complex
NAD + /NADH System
FAD/FADH System
The Cytochrome P450 Cycle
Phase I and Phase II Reactions of Drug Metabolism
Dose-Dependent Toxicity of Acetaminophen
Further Reading
PRINCIPLES OF DRUG–RECEPTOR AND DRUG–ENZYME INTERACTIONS
Drug Receptors and Pharmacodynamics
Mechanisms of Drug Action
Chemical Signaling and Receptor Function
Models of Drug–Receptor Interaction
Affinity and Intrinsic Activity
Agonists, Antagonists, and Partial Agonists
Differential Effects of Agonists
Cholinergic Neurotransmission
Drug-Induced Enzyme Inhibition
Drug Effects Mediated through Enzyme Inhibition
Competitive, Uncompetitive, and Noncompetitive Inhibition
Examples of Drug–Enzyme Interactions
Pharmacological Effects Produced by Transpeptidase-Penicillinase Inhibition
Suicide Inhibition of Enzymes
References
Drug–Receptor Dynamics and Theories
Occupation Theory (Clark)
Modified Occupancy Theory (Ariën)
Rate Theory (Paton)
Relationship between Concentration and Response
Concentration–Effect Curves
Drug Antagonism
Schild’s Equation
What Is the Importance of This Mathematical Relationship?
Irreversible Antagonism
Noncompetitive Antagonism
Partial Agonists
Various Factors That Can Regulate a Drug’s Effect
Efficacy and Potency
Therapeutic Index
Time–Action Curves
Practice Problems
Answers for the Problems
References
Receptor Regulation and Signaling Mechanisms
Spare Receptors
Overshoot
Down Regulation
Other Factors That Can Affect Drug Response
Receptor Signaling and Second Messenger Systems
Hormones Acting through Intracellular Receptors
Receptor-Coupled (Membrane-Bound) Guanylate Cyclase (GC)
Soluble Guanylate Cyclase
Receptors Linked to G-Proteins and Second Messenger Production
Activation of Adenylate Cyclase and G-Protein Function
Downstream cAMP Second Messenger Pathway
Ca++ /Phosphoinositide/PKC Signaling Pathway
What Is the Purpose of G-Proteins or Any Other Second Messenger System?
Ligand-Gated Ion Channels
Signaling through Voltage-Dependent Ion Channels
Ligand-Gated Sodium Channel
Calcium Channels
Location(s) of the voltage-sensitive Ca2+ channels (VSCC):
How Does Calcium Contract the Skeletal Muscles and the Vascular Smooth Muscles?
Chloride Channel
References Index
Biography
Maria A. Hernandez Ph.D., Ph.D. Rathinavelu