Behavioural (year 2) Flashcards
define true abnormal behaviour
behaviour that is abnormal for that species or situation
what is behaviour driven by?
emotional motivations from prior experiences
what is the aim of behavioural pharmacology?
restore the animal to good emotional health
what are the four neurotransmitters that may be involved?
serotonin
dopamine
GABA
noradrenaline
what is the role of serotonin?
regulate mood, appetite and arousal
what is the role of dopamine?
pleasure, memory, emotional regulation
what is the role of GABA?
inhibitory neurotransmitter
what is the role of noradrenaline?
important for learning and facilitation of other neurotransmitters
what are the 5 main group of veterinary psychoactive drugs?
tricyclic antidepressants specific serotonin reuptake inhibitors monoamine oxidase inhibitors benzodiazepines beta blockers
what sort of disorder are tricyclic antidepressants used for?
anxiety
what are 5-HT receptors for?
serotonin
what is the mode of action of tricyclic antidepressants?
block serotonin and noradrenaline transporters to inhibit the reuptake of them and increase their concentrations in the synapse
what will prolonged use of tricyclic antidepressants cause?
down regulation of post-synaptic serotonin and noradrenaline receptors
give some examples of tricyclic antidepressants
amitriptyline, clomipramine, doxepin
what are the adverse effects of tricyclic antidepressants?
sodium and calcium channel blockers so have cardiac effects
also act as anti-histamines and anticholinergics
what disorder can clomipramine be used to treat?
separation anxiety
describe the pharmacokinetics of clomipramine
extensive first pass metabolism
highly plasma protein bound
excreted in the bile
describe the mode of action of specific serotonin reuptake inhibitors
inhibits the reuptake of serotonin meaning it remains in the synapse for longer
how do the side effects of specific serotonin reuptake inhibitors compare with tricyclic antidepressants?
much less binding to other receptors when using specific serotonin reuptake inhibitors so the side effects are less
what is the main drug in the specific serotonin reuptake inhibitors group?
fluoxetine
describe the pharmokinetics of fluoxetine
first pass metabolism after oral administration
highly plasma protein bound
mainly excreted in urine
long elimination half life - 6-8 weeks to reach maximum effect
what is monoamine oxidase and where is it found?
enzyme found in many tissues including the CNS
two forms - MAO-A and MAO-B
what is MAO used to breakdown?
serotonin, noradrenaline and dopamine
which type of MAO is the main enzyme involved in the breakdown of serotonin, noradrenaline and dopamine?
MAO-B
give an example of a monoamine oxidase inhibitor and which type of MAO it inhibits
selegiline
inhibits MAO-B
what is the main use of selegiline?
treat canine cognitive dysfunction
also useful to treat fear associated with low self-confidence
how does selegiline treat canine cognitive dysfunction?
increase free radical scavenging and enhances nerve growth factor synthesis
selegiline also has an effect of catecholamines, what are these effects?
increased release from neurone, inhibits activity of presynaptic receptor, inhibits reuptake
where is selegiline metabolised?
liver
what is the mode of action of benzodiazepines?
facilitate GABA having effects on the hypothalamus and limbic system
what three effects do benzodiazepines have?
anxiolytic, sedative, amnesic
benzodiazepines are better for short term use, why is this?
negative effects on learning due to amnesic
addiction and tolerance can occur
why should benzodiazepines be phased out and not suddenly stopped?
can cause rebound whereby the previous behaviour returns suddenly and potentially more severe
what species should benzodiazepines be avoided in and why?
cats as it can cause fatal hepatic necrosis
give an example of a benzodiazepine used in canines
alprazolam
what are beta blockers used for?
reduce physiological signs of panic and stress in anxiety/anticipation situations
give an example of a beta blocker used in behavioural pharmacology
propanolol
name two anti-epileptic drugs that can be used in behavioural pharmacology
topiramate and imepitoin
what is the mode of action of topiramate and what is it used for?
potentiation of GABA useful in managing compulsive behaviours
what is the mode of action of imepitoin and what is it used for?
partial GABA agonist used in rapid reduction of fear and anxiety
what is a group of sedatives that may be useful in controlling fear? give an example
alpha2 agonist such as dexmedetomidine
what is the mode of action of gabapentin?
blocks release of glutamate by binding presynaptic calcium channels, reduced glutamate in the amygdala is thought to have anxiolytic effects
what is serotonin syndrome?
many of the behaviour drugs increase serotonin however serotonin toxicity can be fatal
side effects include agitation, tachycardia and hyperthermia
