Define stress?
Pathophysiological changes following exposure to diverse physical/chemical/emotional changes
What are the three output stress responses?
Behavioural
Autonomic nervous system
H-P-A axis
Psychological stress can be divided into?
Controllable stress (self made) Uncontrollable stress: external (bereavement) or internal (perfectionism)
Which area of brain regulates fear?
Amygdala
What is the function of the hippocampus?
Memory function
Formation of moods and emotions
Where is Nor-epinepherine synthesised in the brain?
Locus corruleus (reticular formation) (also in the lateral tegmental area)
Which two hormones play a role in physiological adaptations to stress?
CRH
Nor-epi
Where is CRH synthesised?
Paraventricular nucleus
What is the major regulator of the H-P-A?
CRH
What is the most important area of the brain in regards to sympathetic nervous system stress response?
Hypothalamus
Between which vertebral levels is all the sympathetic innervation contained?
T1 - L2
The hypothalamus has strong connections with which two regions in regards to sympathetic nervous output?
Reticular formation within the brainstem (Locus coruleus synthesises Nor-Epi)
Intermediolateral cell column of the spinal cord
Name the two types of sympathetic nervous system ganglia?
Paravertebral (sympathetic chain)
Pre-vertebral (i.e. ceoliac ganglion)
Where do pre-ganglionic sympathetic fibres synapse onto in the adrenal medulla?
Adrenal chromaffin cells
What is the distribution ratio of Epi and nor-Epi from the adrenal medulla?
80:20
What is the clinical set point defining tachycardia?
H.R>100 bpm
What is the cause beneath sinus tachycardia?
Epi release acting on cardiac cells to increase the work of the heart
What is the cause beneath supraventricular tachycardia?
Hyperventilation causing hypercapnia and therefore blood vessels vasoconstrict, as a result the ventricles of the heart must contract with greater force and work harder to maintain blood flow
What is the clinical set point defining hypertension?
140(+)//90(+) mmHg
What drug may be effective in treating the symptoms underlying PTSD and panic disorders?
Propanolol - non specific Beta blocker
