医学ppt课件cholinoceptorblocking

Cholinoceptor Blocking Drugs Classification Base on specific receptor affinities Antimuscarinic agents Antinicotinic agents( consist of ganglion-blockers and neuromuscular junction blockers) Atropine and its alkaloids Atropine Anisodamine Acopolamine chemistry and pharmacokinetics Tertiary amine alkaloid esters of tropic acid Well absorbed from the gut and across the conjunctival membrane Widely distributed Metabolism and excretion Pharmacological Effects Glands Sweat, salivary gland secretion are greatly reduced Bronchial secretion decreased Reduction in gastric secretion and total acid content, especially at doses greater than 1 mg Pharmacological Effects Eye Mydriasis ocular pressure increase cycloplegia 动眼神经的副交感神经支配 毛果芸香碱激动 瞳孔括约肌 M受体 缩瞳 阿托品阻断 瞳孔开大肌 扩瞳 去甲状腺素能神经支配 虹膜(包括瞳孔括约肌和瞳孔开大肌 ) 毛果芸香碱的缩瞳作用 激动 占优 狭窄时眼内 压增高，闭 角型青光眼 （急，慢型 充血性青光 眼） 变性或硬化 时眼内压增 高 开角性 青光眼（慢 性单纯性青 光眼） 睫状体上皮 细胞分泌 血管 渗出 房水 瞳孔 前房前房角间隙 小梁网 巩膜静脉窦 血流 毛果芸香碱的降低眼内压作用 间隙扩大,房 水入循环 毛果芸香碱收 缩瞳孔括约肌 缩瞳虹膜拉紧 虹膜根部变薄 毛果芸香碱 收缩睫状肌 扩张小血管 阿托品扩瞳，虹膜退向四周，前房角 间隙变窄，房水回流受阻，眼内压升高 降低眼内压 正常时晶体较扁平 受睫状肌控制 环状肌辐射状肌 (瞳孔括约肌) 动眼神经兴奋 或毛果芸香碱 动眼神经胆 碱能神经 阿托品 向瞳孔中心收缩悬韧 带，睫状小带放松 睫状肌松弛而退向 外缘，悬韧带拉紧 (瞳孔开大肌) 去甲肾上腺素能 神经支配 对眼 调节无重要意义 只视近物(调节痉挛)只视远物(调节麻痹) 晶状体变扁 屈光度降低 晶状体变凸 屈光度增加 毛果芸香碱的调节痉挛作用 外 界 睫状肌起点 悬韧带 Pharmacological Effects Smooth muscle Gastrointestinal tract: relax Genitourinary tract: relax, void slowly Pharmacological Effects Cardiovascular system: Heart rate:Lower doses: Presynaptic receptor blocked bradycardia At moderate to high therapeutic doses: tachycardia Atrioventricular conduction In toxic concentrations: intraventricular conduction block Pharmacological Effects blood vessel and pressure Vasodilation and hypopiesis caused by cholinnergic nerve can be blocked At toxic doses, cutaneous vasodilation Pharmacological Effects CNS At normal doses, minimal stimulant effect In toxic doses, excitement, agitation, hallucinations and coma Clinical uses Relieve hyperkinesia Inhibit secretion Ophthalmology: iritis, optometry Arrhythmia shock Cholinergic poisoning Clinical uses p 2001年 1月11日 羊城晚报（成都消息） 37岁男性，因家庭纠纷喝乐果中毒。昏迷，每 30分钟用5支阿托品，无效 每10分钟用5支 ，无效 每5分钟用10支，连续使用72小时 ，总共用了1700支，850 mg 病人清醒，生 命体征趋向平稳。（阿托品的 最低致死量为成 人80-130 mg ，儿童10 mg ）。 Adverse effects Dry mouth, mydriasis, tachycardia, hot and flushed skin, agitation and delirium Hyperthermic effects: dangerous when overdose in infants/children CNS: hallucinations, coma Rescue Catharsis Physostigmine CNS: diazepam Anisodamine Pharmacodynamics: similar to atropine Clinical uses: shock Scopolamine CNS: inhibited Take before anaesthesia motion sickness Parkinsons disease 药药 物 扩扩 瞳 作 用 调调 节节 麻 痹 作 用 浓浓 度（ %） 高 峰 （分） 消 退 （日） 高 峰 （小时时） 消 退（ 日） 硫酸阿托品 1.0 304071013712 氢氢溴酸 后马马托品 1.04060120.5112 托吡卡胺 0.5 1.0 2040 1/41/21/4 mydriatic Quaternary antimuscarinic drug: propantheline bromide Triple antimuscarinic drug: Pakinsons disease benactyzine Pirenzepin Block M1, M4 receptor selectively Ulcer, chronic bronchitis NN Cholinoceptor Blocking Drugs ganglionic blocking drugs Mecamylamine, trimetaphan camsilate pharmacodynamics Block N1-receptors in ganglion competitively, decrease blood pressure Small artery Relax, decrease blood vessle resistance Venulae relax, decrease blood volume returing to heart Clinical use Decompression in anesthesia and operation of aortic aneurysm Adverse response Much and severe adverse responses： postural hypotension, retention of urine, etc. N2 Cholinoceptor Blocking Drugs Skeletal muscle relaxants It combines with N2-receptor of motor end-plate on postsynaptic membrane, the transmission of nerve impulse is blocked, leading to skeletal muscle relaxation. divide into two classes on the basis of their mechanism of action Depolarizing muscular relaxants: succinylcholine Nondepolarizing muscular relaxants: d-tubercurarine Depolarizing muscular relaxants Mechnism Binds to Nm receptor Depolarize longer than Ach Depolarization nondepolarization Depolarizing muscular relaxants Quiver before relaxation Acute tolerance Cholinesterase inhibitors can strength its effects Can not block NN-receptors in ganglion Succinylcholine Clinical uses: Guttural muscle are