Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
25 Cards in this Set
- Front
- Back
|
What do local anaesthetics act on? |
local anaesthetics inhibitnerve conduction byblocking sodium channels |
|
|
What are the features of SYMPATHETIC NERVES? |
Pre Ganglionic fibres short, close to CNS. Large distance between pre and post ganglionic elements |
|
|
What are the features of the Parasympathetic nerves? |
Pre ganglionic fibres closer to target tissues |
|
|
What are the features of the MOTOR NERVE? |
Goes to Neuromuscularjunction (NMJ,skeletal muscle) |
|
|
Where is noardrenaline neurotransmitter found? |
Noradrenaline (NA) – sympathetic terminals |
|
|
Where is ACh found? |
Acetylcholine (ACh) – parasympatheticterminals, ganglia& NMJ |
|
|
Where is Dopamine found? |
Dopamine (DA) – parts of CNS |
|
|
Where is serotonin found? |
Serotonin (5-HT) – parts of CNS |
|
|
Where is Nitric oxide (NO) found? |
Various, erectile tissue in particular |
|
|
What is the Anatomy of sympathetic nervoussystem? |
Emanates fromTHORACOLUMBARsegments of spinal cord Ganglia –Typically close to spinalcord in the paravertebralchain |
|
|
What is the Anatomy of parasympathetictransmission? |
TWO IMPORTANT POINTS Craniosacral outflow…… (i) Cranial – oculomotor,facial, glossopharyngeal,vagal (ii) Sacral – nervi erigentes Ganglia –Close to orinside target tissues |
|
|
What happens at the The neuroeffector junction (terminal region)? |
Ation potential ----> depolarisation ----> voltage operatedcalcium channel ---->NT release ----> postsynapticagonism -----> presynapticautoinhibitoryagonism |
|
|
What drugs act on the Synthesis and storage of transmitter? |
INHIBITORY EFFECTS precursor uptake(ACh x by hemicholinium)enzyme cascade(NA x by AMPT) Storage(NA x by reserpine) STIMULATORY EFFECTS provide excessprecursor(L-DOPA/DA) |
|
|
What is L-DOPA used to treat? |
Major Therapeutics: L-DOPA to increasedopamine levels in the brains of patients withParkinson’s disease |
|
|
What drugs affect the Release of transmitter? |
INHIBITION Inhibit terminal depolarisation(NA x by guanethidine; ofminor importance to itsoverall effect) (Ca entry by conotoxin) vesicle fusion(ACh x by Botulinum) presynaptic receptor(NA x by clonidine - α2 adrenergic agonist ) STIMULATION displace NT(NA: byamphetamine andguanethidine) |
|
|
What drugs act on Termination of neurotransmission? |
INHIBITION OF TERMINATION (Note that inhibition oftermination willenhance transmission) inhibit reuptake(NA/cocaine;5-HT/fluoxetine) inhibit enzyme(neostigmine/ACh) |
|
|
What are the mahor therapeutic effects of Prozac? |
Major therapeutics: tricyclic antidepressantsinhibit NA uptake; fluoxetine(Prozac) inhibits 5-HT uptake |
|
|
What are the major therapeutic effects of anticholinesterases? |
Major therapeutics:anticholinesterases to reversemuscle relaxation in surgery |
|
|
What is Agonist and antagonist action on receptors? |
Agonist:affinity and efficacystimulate receptormimic transmitter Antagonist:affinity but no efficacyblock binding siteinhibit transmitter |
|
|
What are the Receptor agonists with majortherapeutic applications? |
Transmitter/Receptor Drug Use Noradrenaline/β2 - salbutamol asthmaNoradrenaline/α1 - phenylephrine decongestantDopamine/D2 - bromocriptine - Parkinson’s Disease Enkephalin/µ - morphine - pain relief GABA/A - diazepam - anxiety |
|
|
What should be noted about diazepam? |
(note diazepam acts on a site different on the receptor from the GABA bindingsite to enhance the effects of GABA – not strictly an agonist) |
|
|
What are the Receptor antagonists with majortherapeutic applications? |
Transmitter/Receptor Drug UseNoradrenaline/α1 - prazosin - reduce BPNoradrenaline/β - propranolol - reduce BPAcetylcholine/nicotinic - atracurium muscle relaxant Acetylcholine/muscarinic - atropine - pre-medDopamine/D2 - trifluoperazine - antipsychotic |
|
|
What are some Drugs affecting the neuroeffector response? |
Benzodiazepine tranquillisers: Bind to the GABA receptor/Cl ionchannel complex to enhancechannel opening and potentiateinhibitory effects of GABA Sildenafil (Viagra): Inhibits breakdown of thesecond messenger substancecyclic GMP produced by nitricoxide in erectile tissue |
|
|
What are the sites of drug action? |
1. synthesis 2. storage 3. release 4. receptors 5. cessation |
|
|
Why is the synapse is an important target for drug action? |
The synapse is an important target for drug action because: • it is the site of neurotransmission • it is the site where the transmitter is synthesised, stored andreleased • it is a major location for receptors and target for agonists orantagonists • receptors offer the best chance of producing drugs with ahigh degree of selectivity and therefore with reduced sideeffect profile |
