Chapter3PharmacodynamicsContentsContents1、Basicaction2、Therapeuticeffect3、Adversereaction4、Dose-effectrelationship5、Mechanismofaction1、BasicactionandPharmacologicaleffectDrugactionPrimaryactiondrugactingbodyeffectsecondactionTwoeffectExcitation:Inhibition:(兴奋)(抑制)正常正常强壮烦躁不安惊厥死亡Excitation镇静催眠麻醉回苏麻痹死亡Inhibitiontwocharacteristics:1)specificity(特异性)drug2)Selectivity(选择性)(tissuebinding)2.Therapeuticeffectthetherapeuticgoal.Favorabletothenormalizationofphysiological,biochemicalfunctions.治疗目标therapeuticeffects1、Etiologicaltreatment2、Symptomatictreatment急則治标,缓则治本标本兼治,不可偏废也治疗效果1)EtiologicaltreatmentAimstoeliminatepathogenicfactore.g.antibiotics-----microbesinfection2)SymptomatictreatmentAimstoallayoramelioratesymptome.g.analgesics---analgesia对因治疗对症治疗isadoubleedgedsword!Drug3.AdversereactionSidereaction(副作用)Accompaniedbythetherapeuticeffect.AppearsatthetherapeuticdoseDependsdrug`sintrinsicaction.Expectable.CanbemoderatedToxicreaction(毒性反应)ResultsfromoverdoseandexcessiveaccumulationofdrugCanbeexpectableShouldbeprevented1)circulationAcuteToxicreaction2)respiratory3)nervous1)liver,kidney3)endocrine2)bonemarrowchronicToxicreaction4)other⑴Carcinogenesis(致癌)chronic4)other⑵Teratogenesis(致畸)⑶Mutagenesis(致突变)血药浓度降至有效浓度以下时残存的效应。Residualeffect(后遗效应)Withdrawalreaction(停药反应)reboundreaction(回跃反应):突然停药后原有疾病加剧。Allergicreaction(变态反应)hypersensitivereaction1)unconcernedwithdose2)varyfromdrugtodrugandpersontoperson(因药而异,因人而异)(过敏反应)(与剂量无关)Idiosyncrasy(特异质反应)先天遗传异常某些药物高敏。glucose-6-phosphatedehydrogenase(葡萄糖-6-磷酸脱氢酶)geneticenzymedefects(遗传的缺陷),Concentration-effectrelationship(浓效关系)Dose-responsecurve(量效曲线)Gradeddose-responsecurve(量反应曲线)Dose-effectrelationship(量效关系)量效关系1.dose/dosage(剂量)用药的分量2、Dose-effectrelationship在一定的范围内药理效应与剂量成正比。3、dose-effectcurve,D-E曲线(量-效曲线)。100%50%E(A)C长尾S型曲线(B)LogC对称S型曲线EmaxEmaxFig3-1药物作用的量效关系曲线E100%50%0.1110300pD2C亲和力指数pD2与亲和力成正比作用强度最小有效量常用量(治疗量)极量最小中毒量最小致死量剂量量效曲线Response(%)concentration10987ECminEmin100%50%EminECmaxEmaxEC50Efficacy(效能)maximaleffect(最大效应).Relativeconcentrationordoseofdrugsinducingequivalenteffects(等效浓度或剂量,EC50)Potency(效价强度):各种利尿药的效价强度和最大效应比较环戊噻嗪氢氯噻嗪呋噻米氯噻嗪质反应的量-效曲线QuantalDose-effectcurves质反应的量-效曲线药物效应和毒性的量效曲线therapeuticindexTITI=LD50ED503治疗指数ED50LD50DrugADrugBAB…………………..…......…….100%50%半数有效量(medianeffectivedose,ED50)ELTI药物安全性评价TI评价药物安全性不完全可靠(certainsafetyfactor,CSF)CSF=LD1/ED991安全范围可靠安全系数ED95~LD5之间的距离结论significanceofdose-effectcurve1)半数有效量(ED50)2)效能(efficacy)3)效价强度(potency)1、评价药效:量效曲线的意义1)半数致死量(LD50)2)治疗指数(therapeuticindex,TI)3)可靠安全系数(certainsafetyfactor,CSF)2、评价药物的安全性评价药物的安全性§3Drug药物与受体receptortosense、recognize、bindsomeminimalchemicalmaterialandTriggerphysiologiorpharmacologicaleffectreceptor?afunctionalproteinreceptordrugendogenousligands配体(内源性配体)1)neurotransmitters神经递质2)hormones激素3)autocoid自体活性物质exogenousligands(外源性配体):drugLigands1)transmitter:Ach,NA,3)autacoid:prostaglandin(前列腺素)histamine(组织胺)Endogenousligands(乙酰胆碱,去甲肾上腺素)2)hormone:adrenocorticoid,(肾上腺皮质激素)insulin(胰岛素),thyroxin(甲状腺素)characteristicsreceptorsensitivity(灵敏性):剂量小specificity(特异性):结构要求高saturability(饱和性):数目有限reversibility(可逆性):结合后可解离multiple-variation(多样性):分布不同,效应不同相互作用Twoimportantfactors1)affinity(亲和力);2)intrinsicactivity,(内在活性α)D+RDR--E(-)(+)Drug-receptorinteractionsaffinity?能力ofD+R?intrinsicactivityD+REAccordingoccupationtheoryD+Rk1k2DR--EKDk1k2[D][R][DR]当全部受体被占领时,效应达最大值Emax,当50%受体与药物结合时,KD=〔D〕Theaffinityisdefinedbythedissociationconstant(解离常数)whichisgiventhesymbolKD.ThehighertheKD,thelowertheaffinity.KD药物与受体的亲和力(反比)pD2affinityindex-lgKDpD2KDcanbeexpressedwithoutusingmolunits.pD2andaffinityareindirectratio(呈正比).亲和力指数intrinsicactivity&efficacy药物与受体结合后激动受体的能力。内在活性与药物的效能成正比。常用α表示,0≦α≦1。内在活性与效能亲和力与内在活性abcE(%)pD2-lgC亲和力:a=b=c内在活性:a﹥b﹥c亲和力:x﹥y﹥z内在活性:x=y=zxyzE(%)10050pD2xpD2ypD2z♥classificationofdrugsactingonthereceptor1、agonist(激动药)1)highaffinity2)highefficacy(i.e.=1).Fullagonists:(部分激动药)1)havehighaffinity2)lowerintrinsicactivity(0﹤α﹤1).partialagonist:antagonist(拮抗药)1)havehighaffinity2)nointrinsicactivity(0﹤α﹤1).Twotypesofantagonist1)competitive2)non-competitive.propertiescompetitiveantagonist1)occupythereceptor2)donotactivatereceptor3)Thecurveisshiftedtotheright竞争性拮抗药竞争性拮抗药AA+BLogC0EBnon-competitiveantagonistpropertiesEmax1)don,toccupythereceptor2)affinity3)nointrinsicactivity(0﹤α﹤1).4)Thecurveisshiftedtotheright非竞争性拮抗药A+BAELogC非竞争性拮抗药Typesofreceptors受体类型1、G蛋白耦联受体(Gprotein-coupledreceptor)2、配体门控离子通道受体(ligand-gatedionchannel)3、酪氨酸激酶受体4、细胞内受体5、其他酶类受体细胞内信号转导第一信使(firstmessenger):多肽类激素、神经递质、细胞因子第二信使(secondmessenger):cAMPcGMP肌醇磷脂钙离子第三信使(thirdmessengers):生长因子转化因子Regulationofreceptor1、Receptordesensitization(脱敏)downregulation(receptordensity)agonist-specificdesentization(sameR)agonist-nonspecificdesentization(otherR)2、Receptorhypersensitization(增敏)up-regulation(receptordensity)Chapter4Factorsaffectingtheeffectsofdrugs影响药物效应的因素1、药物因素药物制剂固体:片剂液体:注射剂软体:软膏、栓剂水乳油给药途径1)静注注射口服2)药物理化性质3)病人情况:昏迷、休克注意给药途径不同药物性质不同硫酸镁PO:导泻、利胆;IM:抗惊厥、抗癫痫IV:降血压1、体外相互作用:配伍禁忌2、体内相互作用药效学:协同、拮抗药动学:A、D、M、E。druginteraction药效学:1)协同作用:1+122)拮抗作用:1+113)相加作用:1+124)无关作用: