lecture 9 - autonomic nervous system Flashcards
What are the 2 key types of homeostatic control?
Neural, endocrine
Which regions of the spinal cord have sympathetic nerve fibres leaving at?
Thoracic and lumbar
Which regions of the spinal cord have parasympathetic nerve fibres leaving at?
Sacral region
What is the key neurotransmitter of the sympathetic nervous system?
Adrenergic neurotransmission - adrenaline, noradrenaline
What is the key neurotransmitter of the parasympathetic nervous system?
Cholinergic neurotransmission - acetylcholine
Which parts of the body have only sympathetic nervous system innervation?
The skin, and blood vessels
What is the relative distance between sympathetic ganglia and the spinal cord?
Close to the cord - long post-ganglionic neurons
What is the relative distance between parasympathetic ganglia and the spinal cord?
Found close to the effector - thus have short post-ganglionic neurons
What is the difference between the neurotransmitter used at the effector organ in the sympathetic and parasympathetic nervous systems?
Parasympathetic uses ACh at terminal junction, while Sympathetic uses noradrenaline, and only uses ACh further upstream
Where do preganglionic fibres of the SNS originate?
The intermedioalteral part of the thoracic/lumbar cord
Where do fibres of the SNS exit the spinal cord?
The ventral horn
What are the ganglia of the SNS?
Paravertebral sympathetic ganglia - sit adjacent to vertebrae
What are the issues/symptoms commonly experienced due to ANS damage from spinal cord injury?
poor temperature control, blood pressure dysfunction, autonomic dysreflexia, bowel/bladder dysfunction
What is the role of sympathetic inputs to the muscles of the bladder?
Inhibits detrusor muscles and keeps sphincters closed.
What is the role of parasympathetic inputs to the muscles of the bladder?
Contracts detrusor and relaxes internal sphincter
