Anxiety and anxiolytics Flashcards
What is anxiety?
An emotional state related to fear.
How is the feeling of anxiety created?
Autonomic activation - the fight or flight mechanism.
What are some of the symptoms of anxiety?
Racing heart, restlessness, palpitations, sweating, increased blood pressure, dry mouth.
What is the cause of chronic anxiety?
An abnormal regulation or function of the stress/fear pathways.
What percentage of people suffer from some form of anxiety disorder?
16-17%.
What environmental factors can increase the risk of developing an anxiety disorder?
Physical and mental abuse, bereavement, desertion, divorce or isolation.
When does anxiety become a problem?
When non-threatening situations are interpreted as threatening and the concern about the stressor are out of proportion. It can be specific fears or more generalised worries.
What are some normal responses to a threat?
Defence behaviours, autonomic reflexes, arousal alertness and increased vigilance, corticosteroid secretion and negative emotions and aggression anger.
What are the two pathways to the stress/fear response?
The high road - going through the cortex and using primary sensory association along with context and memory through the hoppocampus which then goes to the amygdala, or the low road which is straight to the amygdala.
How does the HPA maintain stress responsiveness?
Release of ACTH and cortisol.
How is the hypothalamus involved in the stress response?
It responds to sensory amygdala and hippocampal inputs to adjust the balance of sympathetic/parasympathetic output.
How is the amygdala involved in the stress/fear response?
It sends outputs to the hypothalamus, periaqueductal gray matter and diffuse modulatory systems to result in HPA activation, sympathetic nervous system activation, avoidance behaviours, freezing, defensive postures, increase vigilance, attentiona and aoursal and alertness.
Why are amine systems important in anxiety?
5HT is involved in mood and wellbeing and noradrenaline is involved in alertness and attention.
What parts of the brain are involved in anxiety disorder?
Cortex, hippocampus, amygdala, hypothalamus and basal ganglia/cerebellum.
What are some non-fear related anxiety disorders?
Generalised anxiety disorder, PTSD and premenstrual dysphoric disorder.
What are some fear related anxiety disorders?
Panic disorder, simple phonias, social phobia/anxiety disorder, OCD.
What are the potential causes of anxiety disorders?
Reduced control of brain areas involved in stress or fear, underactivity of 5HT, overactivity of noradrenaline, reduction in GABA inhibition - reduced expression of GABAa receptors.
What are some treatments for anxiety disorders?
Cognitive and behavioural psychotherapy, pharmacotherapy and a combination of the two.
What do beta-adrenoreceptors do?
They treat the symptoms of anxiety and reduce the sympathetic manifestations of stress/fear response. They are useful for treating phobias.
What are some anxiolytic drugs that target 5HT systems?
Buspirone - partial agonist of 5HT1a receptors and antidepressants such as SSRIs and combined noradrenaline and 5HT uptake blockers.
What are benxodiazepines?
They were developed as tranquilisers that result in the loss of fear, hostility and aggressiveness. They provide fast acting relief of anxiety. They act to increase GABAa receptor inhibition.
Where do benzodiazepines bind?
Binding site located between alpha and beta subunits and potentiates endogenous GABA responses. They increase the frequency of hte channel opening and there is a generalised increase in GABA inhibition.
What are some of the adverse effects of benzodiazepines?
Memory impairment, sedation, abuse potential, addictive, withdrawal syndrome such as irritability, cognitive impairment, insomnia, dysphoria and hypersensitivity to light/sound.
