Pharmacology and Therapeutics Flashcards
gastrin is produced by..
G-cell
gastrin stimulates what receptor
CCKbeta receptor
where find CCKbeta receptor
- enterochromaffin like cell
- parietal cell
histamine stimualtes what receptor
H2 receptor
histamine is produced by
enterochromaffin-like cell
what receptor responds to the peripheral nervous system
M1 receptor
where are H2 receptors found
parietal cell
what does the parietal cell produce
H+
epinephrine has what effect on GIT function
inhibits it
Acetylcholine has what effect on GIT function
stimulates it
when does gut smooth muscle fire
spontaneously with slow activity waves
what nerve stimulation increases sphincter tone
sympathetic
what does parasympathetic stimulation do to sphinctal tone
inhibits it
metaclopramide actions
increases Ach release by dopamine antagonism
metaclopramide is a
prokinetic drug
carbachol is a
prokinetic drug
carbachol action
M1 receptor agonist
5 treatments for constipation
- laxitive
- lubricate with liquid paraffin
- give wheat bran or something to bulk up poo and draw water in
- draw water into large intestine
- give irritant to stimulate movement
drugs that draw water into large intestine
- lactulose
- magnesium sulphate
vomiting is stimulated by
chemoreceptor trigger zone (CTZ) in the medulla of the brain
HCl is secreted in response to
- gastrin
- vagal stimulation
pepsin comes from
chief cells
pepsin is secreted in response to
- gastrin
- vagal stimulation
mucous is secreted from
goblet cells
3 phases gastric secretion
- cephalic
- gastric
- intestinal
cephalic phase start
conditioned reflex to smell etc via vagus nerve
cephalic phase actions
HCl, pepsinogen secretion and increased stomach motility
gastric phase actions
chemo and mechano receptors in the stomach release gastrin and histamine
how low pH affects gastric phase
sympathomimetic somatostatin is released which inhibits gastrin secretion
intestinal phase actions
chyme in duodenum causes release of secretin, GIP and CCK which inhibit acid secretion and motility of stomach
prostaglandin analogues inhibit secretion of what in stomach
H+
3 anthelmintic classes based on target parasites
- nematodicide
- cestodicide
- trematodicide
5 broard spectrum anthelmintics
- group 1 - benzimidazoles
- group 2 - imidazothiazoles
- group 3 - macrocyclic lactones
- group 4 amino acetonitrille derivatives
- group 5 - spiroindoles
colour benzimidazoles
white
colour imidazothiazoles
yellow
colour macrocyclic lactones
clear
benzimidazoles actions
- bind to beta-tubulin
- causing inhibition of glucose uptake
- parasite starves to death
imidazothiazoles action
- cholinergic agonist
- rapid and reversible spastic paralysis
example imidazothiazole
levamisole
macrolytic lactones action
- modulate glutamate-gated chloride channels in post synaptic membrane
- flaccid paralysis
metaphylaxis define
used to protect animals grazing on infected pasture
prophylaxis define
used to prevent animals from contaminating pasture
5 groups of narrow spectrum drugs
- salicylanilides
- pyrazinoisoquinolones phenylisothiocyanates
- depsipeptides
- arsenicals
- piperazines
salicylanilides
fluke drenches
pyrazinoisoqunolines phenylisothiocyanates
tape wormers
arsenicals
heart wormers
narrow spectrum flukicides how work
decrease availability of high energy phosphate to the fluke and blood feeding nematodes
main 5 PGE causing nematodes in sheep
- teladorsagia circumcincta
- trichostrongylus spp.
- nematodirus battus
- haemonchus contortus
- cooperia ss
main cow worm
ostertagia ostertagi
main horse worms
strongyles
2 groups strongyles (horse)
- migratory (large)
- non-migratory (cyathostomins)
another name equine strongyles
red worms
underdosing anthelmintics occurs because (4)
- underestimating weight
- inadequate maintenance of equipment
- poor treatment technique
- fail to follow instructions
anthelmintic resistance is detectable when
- over 25% allele frequency
- over 5% parasites are resistant
anthelmintic resistance causes clinical failure when
- allele frequency over 50%
- over 20% worms are resistant
resistance measuring tests (2)
- drench test
- faecal egg count reduction test
drench test how to
- faecal egg count of 10 samples before and after treatment
faecal egg count reduction test how to
- different groups for different drugs and a control group
- faecal egg count before and after dosing
8 SCOPS UK guidelines
- work out a strategy with your vet
- dose only when you need to
- measure resistance on your farm
- reduce your dependence on anthelmintics
- use effective quarantine strategies
- administer anthelmintics effectively
- select the appropriate anthelmintic
- preserve susceptible worms
3 ways to preserve the susceptible worm population
- leave a few animals undosed before moving pasture
- dose animals then leave on contaminated pasture for a while before moving
- alternate sheep and cattle on pasture
define side resistance
resistance to a drug of same group
define cross resistance
resistance to a different drug group with no previous exposure
define glucocorticoid
groups of drugs that have corticosteroid activity
corticosteroids suppress (2)
- inflammation
- adrenal activity
glucocorticoids block synthesis of..
arachidonic acid
as glucocorticoids stop arachidonic acid synthesis they
are better anti-inflammatories than NSAIDs
2 most commonly used glucocorticoids
- prednisolone
- dexamethasome
the order of effects that wear of as glucocorticoid conc decreases
antiinflammatory effect stops before adrenal suppresion
2 phases of treatment of immune mediated disease with glucocorticoids
- induction of remission
- maintenance of remission
side effect of glucocorticoid use
gastric damage
4 quadrants of antimicrobial activity and 1 other
- gram +ve aerobes
- gram -ve aerobes
- obligate anaerobes (gram +ve and -ve)
- penicillinase producing staphylococci
- atypical types
cats haematuria tx
no antibiotics as unlikely to be bacterial unless cat is over 10
dog tx haematuria
antibiotics always given
MIC define
- minimum inhibitory concentration
- the minimum concentration needed to inhibit cell growth
MIC90
the minimum conc needed to inhibit growth in 90% of bacteria
3 drugs that inhibit cell wall synthesis
- penicillins
- cephalosporins
- bacitracin
4 drugs that inhibit cell membrane function
- polymyxins
- amphotericin B
- imidazoles
- nystatin
5 drugs that inhibit protein synthesis
- chloramphenicol
- macrolides
- lincosamides
- tetracycline
- aminoglycosides
2 drugs that inhibit protein synthesis that have toxic affects on animal as well
- tetracycline
- aminoglycosides
5 drugs that inhibit nucleic acid synthesis
- sulphonamides
- trimethoprim
- quinolones
- metronidazole
- rifampin
5 bacteriostatic drugs
- chloramphenicol
- lincosamides
- macrolides
- tetracyclines
- non-potentiated sulphonamides
bacteriostatic effectivness considerations
concentration needs to be maintained to be effective
bacteriostatic actions
inhibits bacterial growth relying on body to kill bacteria
6 bactericidal drugs
- penicillins
- cephalosporins
- aminoglycosides
- fluoroquinolones
- potentiated sulphonamides
- metronidazole
time dependant drug consideration
- need a set amount of time above MIC to be effective
- bacteria need to be multiplying so no bacteriostatic to be used as well
concentration dependent drugs consideration
need a peak concentration
water soluble drugs have
poor perfusion
potentiated sulphonamides are inactivated by
pus