Cholinergic Direct Agonist (PDF)

‫بسم هللا الرحمن الرحيم‬ Pharmacology Lecture (11) Cholinergic agonist : ‫ف الجسم‬Acetyl ‫ي‬ choline‫اماكن وجود الـ ـ...

‫بسم هللا الرحمن الرحيم‬ Pharmacology Lecture (11) Cholinergic agonist : ‫ف الجسم‬Acetyl ‫ي‬ choline‫اماكن وجود الـ ـ‬ 1. nerve ending of para sympathetic 2. sympathetic cholinergic nerve 3. All the ganglia 4. CNS ‫مسؤول عن الذاكره‬ 5. Skeletal muscle (mN) Cholinergic receptors Muscarinic receptors Nicotinic receptors 1. M 1 (mN) and ( nN) 2.M 2 ‫يف مكاني ال ثالث لهما‬ 3.M 3 1. Ganglia 4.M 4 suprarenal glands ‫تشمل الـ ـ ـ‬ 5.M 5 Modified ganglia ‫تعتب‬ ‫النها ر‬ 2. Skeletal muscle  Muscarinic receptors M 1 , M 3 second messenger is Gq Excitatory ‫بالتال غالبا حيكون االثر بتاعهم‬ ‫ي‬ ‫بييد الكالسيوم فاا‬ M 2 CAMP Inhibitory ‫فااا غالبا حتكون‬ M 1 M 2 M gastric M cardiac 1. In stomach 1. heart Function : Leads to HCL 2. CNS ‫ الوظائق حيتم رشحها يف‬Brady cardia CNS ‫سكشن ال‬  M 3 ‫ر‬ ‫اكيهم توزيعا يف الجسم‬ 1. blood vessels (innervated) Act by drugs only Effect: Vasodilation 2. smooth muscle Effect: Contraction in walls Relax in Sphincters : ‫دايما بنحفزو ل امراض‬ ‫االمساك و احتباس البول‬ 3. Glands Increase all secretion  In the EYE 1. Miosis Leads to open the angle of the eye Then the humors will go on 2. That will decrease intra orbicular pressure I.O.P ‫ دا‬receptor ‫عب تحفب ال ـ ـ‬Glaucoma ‫ر‬ ‫ممكن تعالج الـ ـ‬ 3. Near vision. ‫انقباض العي يسبب زياده ُسمك العدسه مما يؤدي ال قرص يف النظر‬ Parasympathomimitic ‫ ر‬Acetyl choline ‫ليه ما عندنا‬ ‫مباشه كدواء للتنشيط ؟‬ Non selective ‫النه‬ Very short duration ‫وعنده‬ ‫ ثانيه فقط‬20 ‫بيقعد يف الجسم‬  Parasympathomimitic Direct In direct 1. Carbachol No drug can release Ach from 2. Bethanechol the nerve ending. 3. pilocarpine 4. cevimeline Otherwise: We only can prevent Ach degradation Direct N receptor By Ach Esterase’s. 1. Nicotine 2. lobeline ‫نادر االستخدام‬ Choline esters are poorly absorbed and poorly distributed into the central nervous system because they are hydrophilic. hydrolyzed in the GiT (and less active by the oral route).  1. Carbachol Synthetic drug  Muscarinic +Nicotinic agonists  For treating glaucoma as eye drops. Bethanechol ‫دواء الحمامات‬ By Oral or subcutaneous only  M agonist It lacks nicotinic actions. In GiT and urinary system.  Treatment of 1. post-operative, postpartum- retention ‫ر‬ :‫بشط‬., non-obstructive urinary retention ‫ما يكون الحبس بسبب عضوي‬ 2.Atonic bladder ‫عدم قدره المثانه عىل االنقباض‬  Pilocarpine Natural Selective M 3 agonist Eye drop for emergency treatments of Glaucoma. side effects Dumbles ‫اختصارا‬  Diarrhea  Urination  Miosis  Bradycardia  Bronchoconstriction  Emesis  Excitation of ANS  Salivation  Nicotinic agonist  Nicotine Natural selective mN receptors. Small dose stimulant Ganglia: 1. Blood vessels V.C Clinical uses: ONLY as patch for: 1. Medical use in smoking cessation. Other uses 1.Smoking and insecticides