Chapter 5 Cholinergic Drugs
Chapter 5 Cholinergic Drugs
Cholinergic Drugs ●Definition -Drugs that stimulate the parasympathetic nervous system (PSNS) -Producing actions similar to that of acetylcholine (ACh) The PSNS is the opposing system to the SNS -Parasympathomimetics/cholinomimetics -Mimic the effects of the PSNS neurotransmitter:acetylcholine (ACh)
Cholinergic Drugs • Definition – Drugs that stimulate the parasympathetic nervous system (PSNS) – Producing actions similar to that of acetylcholine (ACh) – The PSNS is the opposing system to the SNS – Parasympathomimetics/ cholinomimetics – Mimic the effects of the PSNS neurotransmitter: acetylcholine (ACh)
Drug Effects ·The PSNS is the“rest and digest”system ·“SLUDGE -Salivation -Lacrimation -Urinary incontinence -Diarrhea -Gastrointestinal cramps -Emesis
Drug Effects • The PSNS is the “rest and digest” system • “SLUDGE” – Salivation – Lacrimation – Urinary incontinence – Diarrhea – Gastrointestinal cramps – Emesis
Cholinergic Drugs Direct-acting Indirect-acting Receptor agonists Cholinesterase inhibitors Choline ester: Alkaliod: Irreversible: Reversible: Carbachol; Pilocarpine Isoflurophate Neostigmine bethanechol
Cholinergic Drugs Direct-acting Receptor agonists Choline ester: Carbachol; bethanechol Alkaliod: Pilocarpine Indirect-acting Cholinesterase inhibitors Irreversible: Isoflurophate Reversible: Neostigmine
Choline Ester Choline Ester AChE Susceptibility Muscarinic Effect Nicotinic Effect 0 CH3 HgC-C-O-CH2-CH2-N+-CH3 Highest (++++ High (+++ High(+++) CHg Acetylcholine 0 a Hc-c-0Cc-w≤8 Low (+ Highest (++++ None H3 CHa Methacholine (acetyl-B-methylcholine) 0 HN-C-O-CH2-CH-N CHa Negligible Medium (++ High (+++ CHa CH3 Carbachol (carbamoylcholine) 0 CHa Negligible Medium (++ None H2N-C-O-CH-CH2-N+-CH3 CH3 CHa Bethanechol (carbamoyl-B-methylcholine)
AChE Susceptibility Muscarinic Effect Highest (++++) High (+++) Low (+) Highest (++++) Negligible Medium (++) Negligible Medium (++) Choline Ester Choline Ester Nicotinic Effect High(+++) None High (+++) None