Chapter 6 Parasympathomimetics Cholinoceptors Agonists Anticholinesterases
Chapter 6 Parasympathomimetics Cholinoceptors Agonists Anticholinesterases
Sectionl. M-R Agonists choline esters:均含有季铵基团,(MR,NR) acetylcholine(ach): unstable, low selectivity methacholine(醋甲胆碱) carbachol(卡巴胆碱) bethanechol chloride(氯贝胆碱) alkaloidS:(M-R) carpine muscarine arecoline(槟榔碱)
Section1. M-R Agonists choline esters: 均含有季铵基团, (M-R, N-R) acetylcholine (Ach)：unstable, low selectivity methacholine (醋甲胆碱) carbachol (卡巴胆碱) bethanechol chloride (氯贝胆碱) alkaloids: (M-R) pilocarpine muscarine arecoline (槟榔碱)
Choline esters Acetylcholine(Ach,乙酰胆碱) PHarmacological actions Directly activate M, N-R .o muscarinic actions: in small dose nicotinic actions: in large dose Effective in large dose iv Local effect by im, sc
[Pharmacological actions] Directly activate M, N-R ❖ muscarinic actions: in small dose ❖ nicotinic actions: in large dose Acetylcholine (Ach,乙酰胆碱) Effective in large dose iv Local effect by im, sc Choline esters
AUTONOMIC SOMATIC Sympathetic innervation Sympathetic Parasympathetic adrenal dulla Ganglionic transmitter Acetylcholine Acetylcholine Acetylcholine no ganglia Nicotinic Nicotinic Nicotinic Adrenal medulla Postganglionic neurons NeuroeffectorEpinephrine released Norepinephrine Acetylcholine Acetylcholine into the blood Adrenerg Adrenergi Muscarinic receptor receptor receptor 多 NicotinIc Effector organs stue横纹肌 FIgure 3.6 Summary of the neurotransmitters released and the types of receptors found within the autonomic and somatic nervous systems. [Note: This schematic diagram does not show that the parasympathetic ganglia are close to or on the surface of the effector organs and that the postganglionic fibers are usually shorter than the preganglionic fibers
横纹肌
Robert Furchgott 1. muscarinic actions (cardiovascular system vessel dilation,BP↓( reflective HRT)HR↓ a. NO release↑ (M3R→EDRF(NO)↑→GC→cGMP↑→ intracellular Ca2) b. NA release .o Heart depression: atrium>ventricles negative(chronotropic, dromotropic, inotropic) effect Direct effect: mainly in atrium Indirect effect (negative feedback NA release D): ventricles
1. muscarinic actions (1) cardiovascular system ❖ vessel dilation, BP↓ (reflective HR↑) HR a. NO release↑ (M3 R →EDRF(NO) ↑→GC →cGMP↑→ intracellular Ca2+↓) b. NA release↓ ❖ Heart depression: atrium>ventricles negative (chronotropic, dromotropic, inotropic) effect Direct effect: mainly in atrium Indirect effect (negative feedback NA release ↓): ventricles Robert Furchgott