ANS 1 (Parasympathetic) Cholinergic Agonists Flashcards by Kristine Bianca Dagala

Parasympathetic state/ acetylcholine effect and the muscarinic receptor (involved) of heart

Bradycardia; M2 receptor

How well did you know this?

Not at all

Perfectly

Parasympathetic state/ acetylcholine effect and the muscarinic receptor (involved) of lungs

Bronchoconstriction; M2 receptor

How well did you know this?

Not at all

Perfectly

Parasympathetic state/ acetylcholine effect and the muscarinic receptor (involved) of gastric acid secretiond

increased gastric secretion; M1 receptor

How well did you know this?

Not at all

Perfectly

Influx of what ions causes the vesicles to fused with the plasma membrane and releases ACh

How well did you know this?

Not at all

Perfectly

enzyme that breaks down ACh

Acetylcholinesterase (AChE) or cholinestrase

How well did you know this?

Not at all

Perfectly

Cholinergic Agonist or Cholinergic Antagonist: Pilocarpine

Cholinergic Agonist

How well did you know this?

Not at all

Perfectly

Cholinergic Agonist or Cholinergic Antagonist: Scopolamine

Cholinergic Antagonist

How well did you know this?

Not at all

Perfectly

Cholinergic Agonist or Cholinergic Antagonist: Atropine

Cholinergic antagonist

How well did you know this?

Not at all

Perfectly

Cholinergic Agonist or Cholinergic Antagonist: Succinylcholine

Cholinergic antagonist

How well did you know this?

Not at all

Perfectly

Two general groups of cholinergic agonists based on MOA

Direct and indirect Acting

How well did you know this?

Not at all

Perfectly

Brains, spinal cord

Central Nervous system

How well did you know this?

Not at all

Perfectly

nerves outside the brain and spinal cord

Peripheral Nervous System

How well did you know this?

Not at all

Perfectly

Composed of sensory neurons

Conducts signals from receptors to CNS

Sensory or Afferent Division

How well did you know this?

Not at all

Perfectly

Composed of motor neurons

Conducts signals from CNS to effectors

Motor or Efferent Division

How well did you know this?

Not at all

Perfectly

conducts voluntary movement
with stimulatory effect only 
1 neuron
Neurotransmitter: ACh/nicotinic
targets skeletal muscles

Somatic NS

How well did you know this?

Not at all

Perfectly

conducts involuntary or automatic movements
with ganglion (postsynaptic or presynaptic)- 2 neurons
with stimulatory or inhibitory effect (sympathetic or parasymathetic)
Neurotransmitter: ACh/muscarinic or NE/ Alpha or beta
targets smooth muscles glands, adipose tissues

Autonomic NS

How well did you know this?

Not at all

Perfectly

mobilises body systems
“flight or fight” responses
“catabolic” process
Ganglia: near SPINAL CORD ( short Preganglionic & long Postganglionic fibers)
NT:(pre) ACh, (post) NE, E, dopamine
receptors: (ganglia) nicotinic, (target organ) alpha, beta, dopamine

Sympathetic Division/ Adrenergic

How well did you know this?

Not at all

Perfectly

conserves energy
“rest and digest” responses
anaboic process
Ganglia: near TARGET ORGAN ( long preganglionic & short postganglionic fibers)
NT: (pre &post) ACh
Receptor: (ganglia) nicotinic, (target organ) muscarinic, nicotinic

Parasympathetic Division / Cholinergic

How well did you know this?

Not at all

Perfectly

NT:

transmits all parasympathetic signals to end organs by binding to M (muscarinic) receptors
transmits both sympathetic and parasympathetic impulses fr preganglionic neurons to N (nicotinic) recpetors of postganglionic neurons

Acetylcholine (ACh)

How well did you know this?

Not at all

Perfectly

Manifestations of Rest and Digest / Parasympathetic

DUMBBELSS
Diarrhea
Urination
Mydriasis
Bradycardia
Bronchoconstriction
Emesis
Lacrimation
Salivation
Sweating

Erection

How well did you know this?

Not at all

Perfectly

Enzyme needed for synthesis of ACh

choline acetyltransferase (acetyl coa + choline forms ACh)

How well did you know this?

Not at all

Perfectly

transporter needed for choline to enter presynaptic cell needed in synthesis of ACh

Na-dependent choline transporter

How well did you know this?

Not at all

Perfectly

Drug which inhibits ACh to be stored in vesicles

Vesamicol

How well did you know this?

Not at all

Perfectly

ion needed for the release (exocytosis) of ACh to synapse

Calcium

How well did you know this?

Not at all

Perfectly

acetylcholine receptor in postsynaptic cell

Cholinoceptor

enzyme that degrades ACh to acetate and choline thru hydrolysis

Acetylcholinesterase or Cholinesterase

Drug that inhibits transport of choline or synthesis of ACh

Hemicholinium

``` Drug that blocks the release of ACh to synapse Wrinkle treatment (botox) ```

Botulinum toxin (Clostridium botulinum)

Location of M1

``` exocrine glands (secretion) autonomic ganglia (inc seizure activity) CNS ( inc cognitive and function ) ```

Location of M2

Heart (cardiac inhibition) CNS (neural inhibition, inc tremors, hypothermia, analgesia) smooth muscle (inc contraction) Peripheral nerves ( neural inh, dec ganglionic transmission)

Location of M3

``` exocrine glands ( inc secretion) smooth muscles ( inc contraction) eye ( miosis, ocular accommodation) blood vessels: endothelium ( vasodilation) CNS ```

location of M4

CNS (enhanced locomotion)

Location of M5

CNS Salivary glands Iris/ciliary muscle

Location of Nn or Ng (nicotinic ganglionic receptor)

Ganglion ( stimulation) | CNS ( neurotransmission)

Location of Nm (Nicotinic neuromuscular junction)

skeletal muscle (contraction)

2 divisions of Cholinergic agonists

Direct Acting and Indirect acting

2 divisions of direct acting cholinergic agonists

Choline esters and Alkaloids

Drugs under choline esters (choline bound to an acetyl derivative by an ester bond and ester bond is hydrolyzed by cholinesterase or AChE)

``` "Mag- CAB" Methacoline Carbachol ACh Bethanecol ```

Drugs under alkaloids

``` "NAP Muna" Nicotine Arecoline Pilocarpine Muscarine ```

MOA of direct acting cholinergic agonists

drugs directly binds to receptors

most potent cholinergic agonist prototype employed to cause miosis during cataract surgery can produce brief 10 min miosis ester of acetic acid and choline, a quaternary amino alcohol Muscarinic receptors (M1, M2, M3, M4, m5) and Nicotinic

Acetylcholine

T/F: Acetylcholine is selective agonist for different types of cholinoreceptors and has no limited therapeutic use.

FALSE: ACh has both Muscarinic (1-5) and Nicotininc activity therefore, it has LIMITED therapeutic use due to lack of selectivity as an agonist for different types of cholinoreceptors.

T/F: Acetylcholine is rapidly hydrolyzed by cholinesterases.

True

``` Strong muscarinic (1-3) activity (only) specific for GIT and bladder inc intestinal motility after surgery more resistant to hydrolysis acute non-obstructive urinary retention duration: 1hr ```

Bethanechol

ester of carbamic acid has both muscarinic (1-5) and nicotinic activity tx of pilocarpine-resistant open-glaucoma more resistant to AChE/hydrolysis duration: 1hr

Carbachol

has muscarinic (1-3) and weak nicotinic activity Methacoline challenge: diagnosis of asthma reserves for px with Normal Lung Function tests but has Positive asthma symptoms measures hyperresponsiveness / hypersensitivity of the lungs Result: admin of initial, secondary and the highest dose In its highest dose: no asthma if FEV= 20% or higher asthma/hypersensitive lungs if FEV> 20%

Methacholine (Provocholine) | "provoc" Provoking bronchial asthma

T/F: Alkaloids are not metabolized by AChE.

TRUE

DOC for glaucoma exhibits muscarinic (1-3) activity can cross blood-brain barrier

Pilocarpine (alkaloid fr Pilocarpus sp.)

muscarinic (1-3) ; no therapeutic use

Muscarine

muscarinic (1-3) and nicotinic activity | Potential for Alzheimer's

Arecoline

aqueous humor production exceeds outflow, resulting in increased intraocular pressure most common type of glaucoma

Open-angle Glaucoma

(glaucoma-related) ______ causes constriction of the sphicter muscle which surrounds the iris. The iris is drawn away from the Schlemm canal, enhancing outflow of aqueous humor.

Acetylcholine

M(1-5) and nicotinc receptors

ACh, | Carbachol

M(1-3) and nicotinic receptors

Methacoline, | Arecoline

M (1-3) receptors

Bethanechol, Pilocarpine, Muscarine

Divisions under Indirect acting

Organophosphates Carbamates Quaternary Amine (Edrophonium)

highly lipid-soluble liquids have very high affinity for the active site of AChe forming phosphorylated enzyme inactivates enzyme (AChE) thru phosphorylation

Organophosphates

MOA of indirect acting cholinergic agonists

cholinesterase inhibitors

Drugs under Organophosphates

Isofluorophate Echothiophate Malathion, Parathion Tabun, Sarin, Soman

Chronic tx of open-angle glaucoma duration: 1 week route: eye drops

Isofluorophate (DFP: di-isoflurophate)

tx of open-angle glaucoma duration: 3-7 d Route: eye drops

Echothiophate

insecticide/pesticides No clinical use Active metabolites: Malaoxon, Paraoxon

Malathion, Parathion

Used in 1945 as delousing powder and used with soldiers to combat the spread of life thratening diseases like typhus and malaria

DDT (Dichlorodiphenyltrichloroethane)

nerve gases used in chemical warfare poisons of war penetrates skin, eyes, lungs loss of consciousness, seizures , apnea, and death

Tabun(GA), Sarin(GB), Soman (GD)

antidote for organophosphate toxicity or "cholinergic crisrs"

2-PAM (Pralidoxime chloride) , | Atropine

antidote for organophosphate toxicity that inactivates AChE thru dephosphorylation; does not cross the blood brain barrier

2-PAM (Pralidoxime chloride)

antidote for organophosphate toxicity that is a prototype anticholinergic agent and a muscarinic blocker

Atropine

Carbamyl ester inhibitors MOA: carbamyl group prevents ACh from binding to the active site of AChE for a period of min to hours and forms CARBAMYLATED enzyme (can be decarbamlated)

Carbamates

Drugs under carbamates

Physostigmine Neostigmine Pyridostigmine Carbamate Insecticides (CAP)

for intestinal and bladder atony (no muscle tone) mitotic agent for open- angle glaucoma tx of overdoses of anticholinergic drugs ( atropine, TCA, Phenothiazine) duration: 6-12 h

Physostigmine (Eserine)

Physosstigma venenosum can enter and stimulate the CNS inhibit AChE in th eCNS stimulates muscarinic, nicotinic sites of ANS + nicotinic of NMJ

Physostigmine (Eserine)

tx of Myasthenia Gravis (attacking self tissues) , paralytic ileus, or atony of the urinary bladder antidote for Tubocurarine poisoning and other neuromuscular blocking agents direct agonist at NM more polar and does not enter CNS duraion: 3-6h

Neostigmine (Prostigmin)

Symptoms of Myasthenia gravis

``` drooping eyelid difficulty in swallowing slurred speech weak muscles weak breathing muscles ```

MOA of Neostigmin tx for MG:

AChE inh prevent ACh degradation: which increases the probability that remaining receptors will bind ACh

direct agonist activit at NM tx of MG (other than Neostigmine) duration: 4h

Pyridostigmine (Mestinon)

Enumerate: Carbamate insecticides

``` CAP Carbaryl Aldicarb Propoxur increases ACh ```

competitive AChE, which contains QUATERNARY ammonium reversible binding to AChE used for Myasthenia grvis diagnosis (Tensilon test) short duration: 1-2h

Edrophonium (Tensilon)

Effect of Cholinergic antagonist

dec ACh

3 Divisions of Cholinergic Antagonists

Muscarinic Blockers Ganglion BLockers Neuromuscular Blockers

MOA of Muscarinic BLockers

blocks the binding of ACh to muscarinic receptors

ANS 1 (Parasympathetic) Cholinergic Agonists Flashcards

(80 cards)