Lecture 2 Flashcards
What is cardiac output?
Heart rate x stroke volume
What are some points of regulation to change blood pressure?
HR, SV, total peripheral resistance.
If someone weighs 70kg, what would their stroke volume be?
70 ml
Where is the cardiovascular control centre located?
Predominantly the medulla oblongata, some in pons. These are in the brainstem.
The sympathetic centre of the medulla oblongata has what distinct regions?
Augmenter and accelerator.
What are the distinct regions of the parasympathetic centre?
Nucleus vagus and the nucleus ambiguous.
What are some higher brain centres that input into the brainstem cardiovascular control centre?
The hypothalamus, thalamus and cerebral cortex.
What are some stimulus that come to the brainstem from higher centres of the brain?
Anxiety, excitement, exercise and emotion
Other than the higher brain centres, what other inputs does the brainstem receive?
From receptors and reflexes
Is the sympathetic pre-ganglionic fibre long or short?
Short
Where is the ganglion for the sympathetic nervous system and what is it called?
Stellate ganglion at level C6 and C7.
Where do fibres from the right stellate ganglion go?
The the nodal tissue in the heart to control rate
Where do fibres from the left stellate ganglion go to?
Ventricular tissue for contractility
What neurotransmitter controls the heart in the sympathetic nervous system?
NE on beta 1 receptors
What is a positive chronotropic effect?
Increases heart rate
