M受体阻断药阿托品课件.pptVIP

ATROPINE阿托品MUSCARINIC ANTAGONIST Atropine, block muscarinic receptors, causing inhibition of all muscarinic functions. thron apple (曼陀罗)【Source and chemistry】 : alkaloid 生 物 碱 Stramonium 曼陀罗Belladonna 颠茄 【 Mechanism 】: block muscarenic receptors Atropine has a high affinity for muscarinic receptors. Atropine is both a central and peripheral muscarinic blocker. Competition of atropine with acetycholine for the MR 药动学 Absorption: readily Distribution: blood brain barrier Metabolism: partially by the liver Elimination: primarily in the urine Half-life : 4 hoursIts general actions last about 4 hours except when placed topically in the eye, where the action may last for days. 【 Pharmacokinetics 】 ?1.Eye: mydriasis 散瞳 unresponsiveness to light cycloplegia 调节麻痹 intraocular pressure2. Gastrointestinal (Gl ): 胃肠道 Reduce activity of the Gl tract —antispasmodic Hydrochloric acid production is not affectedMYDRIASIS Eye treated with atropineLearn by heart!【 Drug Actions 】 3.Cardiovascular: divergent effects depending on 心血管 the dose Low doses →Cardiac rate (Bradycardia) → blockade of the M1（位于突触前膜）→ACH higher doses → Cardiac rate ( Tachycardia ) →blocked the MR（位于突触后膜） at toxic levels→Arterial blood pressure is affected → dilate the cutaneous vasculature 4.Urinary system: 泌尿系统 Reduce hypermotility states of the urinary bladder5.Secretions: 腺体分泌 Rlocks the salivary glands on the oral mucous membranes → xerostomia Sw