药理学--第二章 药物效应动力学.pptVIP

Chapter 2 药物对机体的作用药效学 Object Pharmacodynamics include: 1. Basic action 2. Therapeutic effect 3. Adverse reaction 4. Dose- effect relationship 5. Mechanism of action §1 Basic action of drug Drug action (药物作用) Adverse reaction (不良反应) unrelated to the therapeutic aim (治疗目的); results in discomfort(不适) or harmful (伤害); expectable, not all could be avoided. (可预见) 1. Side reaction (副反应) At the therapeutic dose ； unrelated to the therapeutic aim； Most slight and expectable (预知) ； can be allayed(减轻). For example: atropine ------ mouth dry, heart-throb (心悸) …… ephedrine ------ CNS(+)…… 2. Toxic reaction (毒性反应) dose is overlarge or over-accumulation (蓄积过多) of drug in the body ; serious reactions ; may be expectable; should be avoided . Latent toxicity (潜在性毒性) Carcinogenesis (致癌作用) 3. residual effect (后遗效应) after the withdraw (停药) the threshold concentration (阈浓度) e.g Barbital 5. allergic reaction (变态反应) unrelated to the dose and their intrinsic effects (原有效应); considerable variety of severity ; pharmacological antagonist (药理性拮抗剂) couldn’t rescue this reaction; often occur in hypersensitive (过敏) person. e.g penicillin 6. Idiosyncrasy (特异质反应) connate genetic abnormity (先天遗传异常); Related to intrinsic action and dose of drug; §2 Drug and receptor What`s receptor? 1. Nature------ a functional protein 2.Function---- to sense、recognize(识别)、 bind some minimal chemical material and transform it into a signal (信号) ， transmit the signal between cells. What`s a ligand (配体)? A material in body to bind the receptor specially. first messenger (第一信使) The characteristics of receptor Sensitivity (灵敏性) Specificity (特异性) Saturability (饱和性) Reversibility (可逆性) Multiple-variation (多样性) Drug - receptor interaction Drug-receptor dynamics According occupation theory(占领学说) Two important factors: kD (affinity) kD is larger, affinity is lower pD2 (index of affi