Pharmacology - Ans

Front 1

What are the effects of stimulation of sympathetic system?

Back 1

- Increase heart rate and blood pressure
- Mobilize energy stores of the body
- Increase blood flow to skeletal muscles and the heart
- Divert blood from skin and internal organs
- Dilation of pupils and bronchioles

Front 2

What are functions of the parasympathetic nervous system?

Back 2

- Maintains essential bodily functions such as digestive processes and elimination of wastes

Front 3

What organs receive only sympathetic innervation?

Back 3

Adrenal medulla, kidney, pilomotor muscles, and sweat glands

Front 4

What are the primary neurotransmitters of the ANS?

Back 4

Acetylcholine and Norepinephrine

Front 5

What is a cholinergic neuron?
What is an adrenergic neuron?

Back 5

A cholinergic neuron is one in which transmission is mediated by ACh.
An adrenergic neuron is one in which transmission is mediated by NE or E.

Front 6

Which drug inhibits synthesis of ACh by blocking transport?

Back 6

Hemicholinium

Front 7

What is the rate-limiting step of ACh synthesis?

Back 7

Uptake of choline from extracellular fluid into cytoplasm.

Front 8

Which drug prevents the release of ACh from the presynaptic neuron?

Back 8

Botulinum toxin.

Front 9

What are the classes of muscarinic receptors?
Which lead to cellular excitation?
Which lead to inhibit excitation?

Back 9

M1, M2, M3, M4, M5.
M1, M3, and M5 generally lead to cellular excitation.
M2 and M4 inhibit cellular excitability.

Front 10

Which muscarinic receptor can you find on gastric parietal cells? Cardiac cells and smooth muscle? Bladder, exocrine glands, and smooth muscle?

Back 10

M1
M2
M3

Front 11

What G protein can be found on M1 and M3 receptors?
On M2 receptors?

Back 11

Gq proteins (which activate phospholipase C and increase intracellular Ca) are activated by M1 and M3 receptors.
Gi proteins (which inhibit adenylyl cyclase increase K conductance) are activated by M2 receptors on cardiac muscle.

Front 12

How do nicotinic receptors function?

Back 12

They function as ligand-gated channels that allow entry of sodium ions.

Front 13

What effects does ACh have on heart rate? Cardiac output? Blood pressure? GI?

Back 13

ACh decreases heart rate and cardiac output. It also decreases blood pressure.
In GI, ACh increases salivary secretion and stimulates intestinal secretions and motility.

Front 14

What are three direct-acting cholinergic agonists?
Which preferentially bind to muscarinic receptors?

Back 14

Bethanechol
Carbachol
Pilocarpine

Pilocarpine and bethanechol preferentially bind to muscarinic receptors.

Front 15

What actions does bethanechol have as a direct-acting cholinergic agonist?

Back 15

Bethanechol directly stimulates muscarinic receptors, causing increased intestinal motility and tone. It also stimulates the detrusor muscles of the bladder, causing expulsion of urine.

Front 16

What are the therapeutic applications of bethanechol?
What are the adverse effects?

Back 16

Used to stimulate the atonic bladder.

Bethanechol causes the effects of generalized cholinergic stimulation
- sweating
- salivation
- flushing
- decreased blood pressure
- nausea
- abdominal pain
- diarrhea
- bronchospasm

Front 17

Does carbachol activate muscarinic or nicotinic receptors?

Back 17

Both.

Front 18

What are the actions of carbachol?

Back 18

May first profoundly stimulate, and then depress, cardiovascular system and GI system.
Can cause release of epinephrine from adrenal medulla.
Can cause miosis (contraction of pupil) and spasm of accomodation

Front 19

What are the therapeutic applications of carbachol?
What are the adverse effects?

Back 19

Used as a miotic agent to treat glaucoma by causing pupillary contraction and a decrease in intraocular pressure.

There are no side effects at normal doses.

Front 20

What are the actions of pilocarpine?

Back 20

Applied to cornea, pilocarpine produces rapid miosis and contraction of ciliary muscle.
Potent stimulator of secretions (sweat, tears, saliva)

Front 21

What are the therapeutic applications of carbachol?
What are the adverse effects?

Back 21

DOC for emergency treatment of narrow-angle and wide-angle glaucoma. Pilocarpine is extremely effective in opening the trabecular meshwork around Schlemm canal, causing an immediate drop in intraocular pressure as a result of the increased drainage of aqueous humor.

Pilocarpine can enter the brain and cause CNS disturbances. Stimulates profuse sweating and salivation.

Front 22

What are the reversible anticholinesterases?

Back 22

Physostigmine
Neostigmine
Pyridostigmine and ambenomium
Edrophonium
Tacrine, donezepil, rivastigmine, galantamine

Front 23

What are the therapeutic uses of physostigmine?
Adverse effects?

Back 23

Physostigmine increases intestinal and bladder motility.
Produces miosis and spasm of accommodation as well as lowering intraocular pressure, treating glaucoma.
Used in the treatment of overdoses of drugs with anticholinergic actions
- Atropine
- Phenothiazines
- Tricyclic antidepressants

Adverse effects include:
- CNS effects such as convulsions
- Bradycardia and fall in cardiac output
- Accumulation of ACh in NMJ results in paralysis of skeletal muscle

Front 24

What are the therapeutic uses of neostigmine?
Adverse effects?

Back 24

Similar to physostigmine, but does not enter CNS and is more effective on skeletal muscle.
- Stimulates bladder and GI tract
- Symptomatic treatment of myasthenia gravis
- Antidote for tubocurarine and other competitive neuromuscular blocking agents.

Adverse effects include generalized cholinergic stimulation such as:
- salivation
- flushing
- decreased BP
- nausea
- abdominal pain
- diarrhea
- bronchospasm

Front 25

What is isoflurophate?
What is its mechanism of action?

Back 25

Isoflurophate is an irreversible anticholinesterase. It covalently binds to the active site of acetylcholinesterase.

Front 26

What are its effects?
Therapeutic uses?

Back 26

Actions include generalized cholinergic stimulation, paralysis of motor function (breathing difficulties), and convulsions. Produces intense miosis.

Used for chronic treatment of open-angle glaucoma (long lasting)

Front 27

Which of the agonists are uncharged, allowing them to penetrate into CNS?

Back 27

Pilocarpine and physostigmine.

Front 28

What are organophosphates?
How do you treat it?

Back 28

They irreversibly bind to acetylcholinesterase and can cause a cholinergic crisis.
Treat with atropine (which blocks muscarinic sites) and 2-PAM (pralidoxime) to reactivate the enzyme.

Front 29

Which drug is used for diagnosis of myasthenia gravis?

Back 29

Edrophonium, a short acting inhibitor of AChE.

Front 30

What are the effects of antimuscarinic agents?

Back 30

They interrupt the effects of parasympathetic stimulation, allowing the actions of sympathetic stimulation to be left unopposed.
Because they do not block nicotinic receptors, the antimuscarinic drugs have little or no action at skeletal NMJ or autonomic ganglia.

Front 31

What are the effects of Atropine on the eye, GI, urinary system, cardiovascular system, and secretions?

Back 31

Eye: Atropine blocks all cholinergic activity on the eye, resulting in persistent mydriasis (dilation), unresponsiveness to light, and cycloplegia (inability to focus for near vision)

GI: Reduces the activity of GI tract. Does not affect HCl production, so it is not effective in promoting healing of peptic ulcer.

Urinary system: Reduces hypermotility states of bladder (i.e. bed wetting)

CV: At low doses, bradycardia (due to blockade of M1 receptors on inhibitory prejunctional neurons). At higher doses, M2 receptors on SA node are blocked, and cardiac rate increases.

Secretions: Blocks salivary glands, producing oral dryness. Sweat and lacrimal glands affected as well.

Front 32

What are adverse effects of atropine?

Back 32

Depending on the dose, atropine may cause dry mouth, blurred vision, "sandy eyes", tachycardia and constipation.
CNS effects include restlessness, confusion, hallucinations, delirium. May progress to depression, collapse of the circulatory and respiratory systems, and death.

Front 33

What are effects of scopolamine?

Back 33

Scopolamine is a very effective anti-motion sickness drug. It also has the unusual effect of blocking short term memory.
At lower doses, it produces sedation.
Produces peripheral effects similar to atropine.

Front 34

What are ganglionic blockers?

Back 34

They specifically act on the nicotinic receptors of both parasympathetic and sympathetic autonomic ganglia. Thus, these drugs block the entire output of the ANS at the nicotinic receptor.

Front 35

What is trimethaphan used for?

Back 35

Trimethaphan is a short-acting, competitive nicotinic ganglionic blocker that is used for emergency lowering of blood pressure.

Front 36

What are neuromuscular blocking drugs?

Back 36

These drugs block cholinergic transmission in the NMJ.

Front 37

What are the effects of tubocurarine?

Back 37

Tubocurarine, a nondepolarizing (competitive) blocker, binds with the nicotinic receptor and prevents binding of ACh.
It is used during surgery to relax skeletal muscle.

Front 38

What are the effects of succinylcholine?

Back 38

Succinylcholine, a depolarizing neuromuscular blocking drug, attaches to the nicotinic receptor and acts like ACh to depolarize the junction. The drug remains at the receptor, and results in resistance to depolarization.
It is used during rapid endotracheal intubation is required during induction of anesthesia.

Front 39

What are the differences between alpha 1 and alpha 2 adrenergic receptors?

Back 39

Alpha 1 receptors:
- present on the postsynaptic membrane
- constriction of smooth muscle
- Qq protein

Alpha 2 receptors:
- primarily located on presynaptic nerve endings and on beta cells of pancreas
- control adrenergic neuromediator and insulin output
- feedback inhibition of NE release
- Gi protein