Cholinergic Agonists

Cathecolamines

• A type of neurohormone

• are important in stress responses

Cathecolamines

• High levels cause high blood pressure which can lead to headaches, sweating, pounding of the heart, pain in the chest, and axiety

Neurohormones

• a chemical that is made by nerve cells and used to send signals to other cells

Adrenaline

• fight or flight

• produced in stressful situations

• increases heart rate and blood flow, leading to physical boost and heightened awareness

Noradrenaline

• concentration

• affects attention and responding actions in the brain

• contracts blood vessels, increasing blood flow

Dopamine

• pleasure

• also addiction, movement and motivation

• people repeat behaviors that lead to _____ release

Serotonin

• mood

• contributes to well-being and happiness

• helps sleep cycle and digestive system regulation

• affected by exercise and light exposure

Gaba

• calming

• calms firing nerves in the CNS

• high levels improve focus, low levels cause anxiety

• contributes to motor control vision

Acetylcholine

• learning

• involved in thought, learning and memory

• activates muscle action in the body

• also associated with attention and awakening

Glutamate

• memory

• most common neurotransmitter

• involved in learning and memory, regulates development and creation of nerve contacts

Endorphins

• euphoria

• released during exercise

• excitment and sex

• producing well-being and euphoria

• reducing pain

Lithium and Memantine

Drugs that affects Glutamate

Tyrosine

• amino acid

• precursor of catecholamines

Nerve terminal

The synthesis of NE happens in the:

Tyrosine Hydroxylase or TOH

• the rate limiting enzyme of Tyrosine

Metyrosine

Sympathetic:

• Blocks the origin

Reserpine

Sympathetic:

• Blocks the Storage

Guanadrel, Guanethidin, Bretylium

Sympathetic:

• Blocks the Release

Cathecol-O-Methyltransferase and Monoamine Oxidase

These enzymes Metabolizes NE:

Tricyclic Antridepressants and Selective Serotonin Reuptake Inhibitors

These drugs affects the reuptake of our NE:

Sympathetic

What nervous system division is being described?

Radial muscle: contraction (mydriasis) = increases entrace of light

Ciliary muscle: relaxation = cycloplegia = paralysis of accomodation

Mydriasis

• increased entrance of light

• radial muscle contraction

Cycloplegia

• ciliary muscle relaxation

• paralysis of accomodation

Acetyl COA and Choline

Origin of ACh:

Choline acetyltransferase

• a rate limiting enzyme of ACh

Acetate and Choline

When the ACh is released from the vesicle, it is brokedown into:

Acetylcholinesterase (AChE)

• degrades the choline / acetate during its reuptaking or reabsorption:

Hemicholinum

Parasympathetic:

• blocks the origin

Vesamicol

Parasympathetic:

• Blocks the Storage:

Botulinum toxin

Parasympathetic:

• Blocks the Release

Esterification

• process of destroying ACh

Parasympathetic

What nervous system division is being described?

• Circular muscle - contraction (Miosis) pupiliary constriction

• Ciliary muscle - contraction = Accomodation ( seeing far object near, to be clear, squinting)

Miosis

• Circular muscle contraction

• pupilary constriction

Accomodation

• ciliary muscle contraction

• seeing a far object to be clear

• squinting

Sympathomimetic

• adrogenic agonist

Sympatholytic

• adrenergic antagonist

Parasympathomimetic

• cholinergic agonist

Parasympatholytic

• cholinergic antagonist

Parasympathetic

Effect:

• adrenergic blocker = sympatholytic

Parasympathetic

Effect:

• Cholinomimetic

• Parasympathomimetic

Sympathetic

• Muscarinic Blocker

• Parasympatholytic

Epinephrine

Activates:

• a1, a2, b1, b2

Norepinephrine

Activates:

• a1, a2, b2

Dopamine

Activates:

• a, b , d

2-5 mcg/kg/day

What dose of dopamine activates Dopamine-1?

> 5-10 mcg/kg/day

What does of Dopamine activates Dopamine-1 and Beta-1?

> 10 mcg/kg/day

What dose of dopamine activates Dopamine-1, Beta-1 and Alpha-1?

Pilocarpine

• is a nonselective muscarinic agonist used to treat xerostomia and glaucoma

Muscarinic receptors

• belongs to the class of G protein-coupled receptors

• metabotropic receptors

Nicotinic receptors

• composed of 5 subunits and it functions as a ligand-gated ion channel

• ionotropic receptor

Cholinergic agonists

• mimic the effects of ACh by binding directly to cholinoreceptors (muscarinic and nicotinic)

Muscarinic receptors and Nicotinic receptors

• Two families of cholinoreceptors or cholingergic receptors:

choline esters and naturally occurring alkaloids

• two classifications of direct-acting cholinergic receptors:

Acetylcholine

• is a quaternary ammonium compound that cannot penetrate the membranes

• lacks therapeutic importance because of its multiplicity of actions and its rapid inactivation of cholinesterases

• has both muscarinic and nicotinic activity

Acetylcholine

• decrease in heart rate and cardiac action

• decrease in blood pressure

• increases salivary secretion, gastric acid secretion

Bethanechol

• is an unsubstituted carbomyl ester, structurally related to ACh

• not hydrolyzed by AChE due to the esterification of carbamic acid

Bethanechol

• in urologic treatment, this is used to stimulate atonic bladder, particularly in postpartum or postoperative, nonobstructive urinary retention

• may also be used to treat neurogenic atony as well as megacolon

Carbachol

• has both muscarinic and nictonic actions

• an ester of carbamic acid and a poor substrate of AChE

• bio transformed by other esterases, but at much slower rate

Pilocarpine

• is a tertiary amine and is stable to hydrolysis by AChE

• compared with ACh and its derivates, it is far less potent but is uncharged and can penetrate the CNS at therapuetic doses

Pilocarpine

• can cause blurred vision, night blindness, and brow ache

• poisoning with this agent is characterized by exaggeration of various parasympathetic effects