药理学总论-绪言

药理学总论-绪言 PharmacologyPharmacology A Very Basic Intro What is a drug? - any chemical agent which affects any biological process Sources of Drugs Animals Plants Minerals Synthetic Microbes Genetic engineering drugs 基因工程药物过程示意图 从细胞中分从细胞中分 离出离出DNADNA 限制酶截取限制酶截取 DNADNA片断片断 分离大肠杆分离大肠杆 菌中的质粒菌中的质粒 DNADNA重组重组 用重组质粒用重组质粒 转化大肠杆菌转化大肠杆菌 培养大肠杆菌培养大肠杆菌 克隆大量基因克隆大量基因 nA goal of Genomics is to find and express genes that code for unknown peptides with significant biological properties, like receptors or enzymes. In a reverse Pharmacology approach this peptide, e.g. a receptor, is then used to “fish“ for a natural ligand . With receptor and ligand in hand the biological role of the receptor needs to be determined. Finally, screening for synthetic ligands as well as lead optimization can lead to new drug candidates. In contrast, the classical approach to drug discovery starts with the identification of a ligand that has biological activity that in turn is used to “fish“ for the corresponding receptor. nOne example for a Genomics strategy aims at identifying drug targets based on molecular homology within Gene-families. One of the most important families of drug-targets for the pharmaceutical industry is the family of G-protein coupled receptors (GPCRs). Of the top 200 best selling prescription drugs, more than 20% interact with GPCRs, providing worldwide sales of over $20 billion. The characteristic motif of the GPCR family is the seven distinct hydrophobic regions, each of 20 to 30 amino acids that form the transmembrane domain of these integral membrane proteins. This key amino-acid sequence motif can be found within all types of GPCRs and can be used to identify DNA- sequences that code for GPCRs. What is pharmacology ? - the study of how drugs effect biological systems What is Pharmacology ? Pharmacology Pharmacokinetics Pharmacodynamics What the body does to drug What the drug does to body Pharmacotherapeutics Pharmacocognosy The study of the use of drugs Identifying crude materials as drugs Toxicology Pharmacokinetics What the body does to the drug - Absorption - Distribution - Metabolism (Biotransformation) - Excretion Half-life (t1/2) - the time required for the plasma concentration of a drug to be reduced by 50 % DRUG CLASSIFICATION - Based on the chemical structure - Based on the main effect (e.g. analgesics). - Based on the therapeutic use (e.g. antipsychotic 安定药). -Based on mechanism of action (e.g. serotonin agonist). From Chemist to First In Man approximately 7 10 years How a Drug becomes a drug H. Haarmann University of Maryland, 2002 Basic & Clinical Evaluation of New Drugs 1.Drug discovery & Drug screening 2.Chemistry 3.In Vitro Studies 4.Function in cells, tissues, and at receptors 2. Preclinical safety & toxicity testing In Vivo - Animal studies Pharmacology and Behavioral Pharmacology Potency and Efficacy ED50 Tolerance and Tachyphylaxis(快速耐受) Toxicity Acute and Chronic LD50 Teratogenicity = birth defects Carcinogenicity = cancerous 3. Evaluation of drug in humans Evaluating Drugs in Humans The Food and Drug Administration (FDA) Phases of a Clinical Trials Phase I Phase II Phase III Phase IV Evaluating Drugs in Humans Phase I Healthy adult volunteers Evaluation of safety, Pharmacokinetics (PK), side effects? Phase II - Patients Evaluation of efficacy, safety, PK, and side effects Double-blind placebo controlled Phase III Specific patient subpopulations Determine efficacy for specific indications Large sample of specific patients (1,000) Randomized double-blind placebo controlled Phase IV Post FDA Approval Determine efficacy for specific indication Determine drug utilization patterns and additional efficacy Monitor rare, severe side effects/toxicity Drug Nomenclature -Chemical name（化学名）- *Generic name （非专利 名） - Trade name （商品名） Chemical Name: 2-(4-isobutylphenyl)-propionic acid Generic Name: ibuprofen（