Autonomic Neurotransmission- Cholinergic transmission Flashcards

Question

What drugs can be used to treat glaucoma?

Answer 1

- Cholinoreceptor-activating drugs = carbachol (more possibilities)

Answer 2

1) With a quaternary ammonium group (N+) - Neostigmine - Pyridostigmine - Poor absorption: ◦ Much higher doses are required for oral administration than for parenteral injection - Do not cross the BBB ``` 2)With a tertiary ammonium group • Galantamine • Donepezil • Rivastigmine - Good absorption - Cross the BBB ``` ``` • Organophosphates (insecticides, chemical warfare “nerve gases”) - Good absorption from the GIT, lungs, skin, and conjunctiva - Heavy poisoning ```

Answer 3

1) With a quaternary ammonium group (N+) - Neostigmine - Pyridostigmine - Poor absorption: ◦ Much higher doses are required for oral administration than for parenteral injection - Do not cross the BBB

Answer 4

``` 2)With a tertiary ammonium group • Galantamine • Donepezil • Rivastigmine - Good absorption - Cross the BBB ``` ``` • Organophosphates (insecticides, chemical warfare “nerve gases”) - Good absorption from the GIT, lungs, skin, and conjunctiva - Heavy poisoning ```

Answer 5

- potentiate the actions of the endogenous ACh

Answer 6

•M-cholinomimetic (muscarinic) effects: ◦ Eye: myosis, accommodation, ↓IOP ◦ Heart: bradycardia, ↓ AV conductance ◦ RS: Contraction of the smooth muscle of the bronchial tree and increased secretion of bronchial glands ◦ GIT: stimulation of salivary glands, increased acid secretion, increased secretion of intestinal glands, increased motor activity of the gut, sphincter relaxation ◦ Urinary bladder: stimulation of the detrusor muscle, relaxation of the sphincter, thus promotion of voiding

Answer 7

◦ Depolarization of the endplates – increased contraction of the skeletal muscle

Answer 8

only the lipid-soluble part ◦ In low concentrations – Activation of the EEG ◦ In higher concentrations – Generalized convulsions -> coma and respiratory arrest

Answer 9

- Glaucoma - Postoperative ileus (atony and paralysis of the stomach and bowel following surgical manipulation) - Urinary retention ◦ Postoperative atony ◦ Postpartum ◦ Secondary to spinal cord injury - Myasthenia gravis - Curare-induced neuromuscular paralysis (overdose of nondepolarizing neuromuscular junction blockers) - Atropine intoxication (Galantamine) - Alzheimer’s disease (Donepezil, Rivastigmine)

Answer 10

Contraindications ◦ Ulcer disease ◦ Bronchial asthma ◦ Obstructive ileus Toxicity ◦ Eye: myosis ◦ Glands: sweating ◦ GIT: salivation, vomiting, diarrhea ◦ CVS: bradycardia, AV block, hypotension ◦ RS: bronchoconstriction ◦ Depolarizing neuromuscular blockade: paralysis Treatment of the intoxication: ◦ Atropine ◦ Obidoxime

Answer 11

Drug: ◦ Pilocarpine – plant alkaloid Mechanism of action: ◦ Agonist of М receptors (direct interaction) Clinical use: ◦ For decrease of IOP

Answer 12

Natural alcaloids: ◦ Atropine (from Atropa belladonna) ◦ Scopolamine (Hyoscine) (from Datura stramonium) Drugs: Natural ◦ Atropine ◦ Scopolamine Semi-synthetic ◦ Butylscopolamine Synthetic ◦ Mydriatics Cyclopentolate ◦ Bronchospasmolytics Ipratropium Tiotropium ◦ Urospasmolytics Oxybutynin Solifenacin Darifenacin (selective for M3 receptors)

Answer 13

Good oral absorption and absorption through the conjunctiva Good tissue distribution Short t1/2 ~ 2 h Renal excretion ~ 60% unchanged Effect in the eye >72 h

Answer 14

Eye: • Mydriasis (duration: days) • Cycloplegia (paralysis of the ciliary muscle resulting in a loss of accommodation) • ↑ IOP (dangerous in glaucoma) • Reduction of lacrimal secretion (dry or “sandy” eyes) Heart: • SA node: tachycardia • Improvement of AV conductance RS: • Bronchial muscle: relaxation • Bronchial glands: ↓ secretion Digestive system: • Stomach and intestines: ↓ motility, spasmolytic effect • Gallbladder and biliary ducts: spasmolytic effect • Glands: ↓ secretion of salivary glands (xerostomia, dry mouth) > intestinal glands > gastric glands

Answer 15

Genitourinary tract: * Urinary bladder: relaxation of the bladder wall – slow * Ureters: relaxation of the smooth muscle, spasmolytic effect

Answer 16

In ophthalmology: ◦ For pupil dilation (mydriasis) ◦ For accurate measurement of refractive error in young children (loss of accommodation) For treatment of sinus bradycardia, e.g. acute MI As a spasmolytic agent for gastro-intestinal, biliary and renal colics As a premedication in general surgery (↓ bronchial secretion) ``` For the treatment of poisoning with: ◦ Organophosphates (large doses!) ◦ Mushrooms: ◦ Amanita muscaria ◦ Amanita phalloides ```

Answer 17

``` Adverse effects: ◦ Dry mouth (xerostomia) ◦ Constipation ◦ Blurred vision ◦ Tachycardia ``` ``` Тoxic effects: ◦ CNS: agitation, delirium ◦ Hot and flushed skin ◦ Elevated body temperature “dry as a bone, blind as a bat, red as a beet, mad as a hatter” ``` Contraindications: ◦ Glaucoma ◦ Benign prostatic hyperplasia

Answer 18

``` Muscarinic antagonist - plant origin Scopolamine (hyoscine) ◦ Sedation ◦ Antiemetic effect (М-rec. in the vestibular apparatus and in the vomiting center) ◦ For motion sickness (kinetosis) ```

Answer 19

Muscarinic antagonist - synthetic drugs -> bronchospasmolytics ``` Ipratropium, Tiotropium ◦ Bronchodilatatory effect, for inhalation ◦ Treatment of bronchial asthma and COPD ```

Answer 20

Muscarinic antagonist - semi-synthetic drug ``` Butylscopolamine ◦ A derivative of scopolamine with a quaternary ammonium group ◦ Spasmolytic action ◦ For gastrointestinal, biliary and renal colics ```

Answer 21

Muscarinic antagonist - mydriatics | causes Mydriasis

Answer 22

Muscarinic antagonists - urospasmolytics ``` Oxybutynin, Solifenacin, Darifenacin ◦ Relaxation of the urinary bladder ◦ For the treatment of urinary incontinence in adults ```

Answer 23

Agonists of nicotinic receptors ◦ Nicotine, Cytisine ◦ Usage: ◦ For smoking cessation

Answer 24

``` Antagonists of nicotinic receptors ◦ Ganglion-blocking drugs ◦ Not used nowadays in Bulgaria ◦ Neuromuscular blocking drugs ◦ Non-depolarizing Pipecuronium Atracurium ```

Answer 25

Antagonists of nicotinic receptors ◦ Ganglion-blocking drugs ◦ Not used nowadays in Bulgaria Depolarizing Suxamethonium

Autonomic Neurotransmission- Cholinergic transmission Flashcards

(49 cards)