Lecture 30: Autonomic Control Flashcards
How many neurons are there between the CNS and effector in the somatic pathway?
1
How many neurons are there between the CNS and effector in the autonomic pathway?
2
What do autonomic nerves innervate?
Smooth muscle, cardiac muscle, glands, GI neurons.
Are all somatic and autonomic nerves excitatory?
No, some AUTONOMIC nerves are inhibitory
Which region do sympathetic pre-ganglionic neurons emerge from?
Thoracolumbar.
Which region do parasympathetic pre-ganglionic neurons emerge from?
Craniosacral.
Which neurotransmitter is used in the majority of sympathetic nerves?
ACh @ the pre ganglionic neuron, NE @ the postganglionic neuron.
What are cholinergic and adrenergic neurons?
Neurons that release ACh and NE, respectively.
______ nerves have a short preganglionic axon and long postganglionic axon, whereas _____ nerves have a long preganglionic axon and a short postganglionic axon.
Sympathetic nerves have a short preganglionic axon and long postganglionic axon, whereas Parasympathetic nerves have a long preganglionic axon and a short postganglionic axon.
Which nerve pathways are sympathetic but don’t release NE?
Nerves which innervate the skin: sweat glands and hairs.
Which neurotransmitter is released at parasympathetic synapses?
ACh at both.
What is an ionotropic receptor?
A post synaptic receptor which is contains an ion channel; nicotinic cholinergic and depolarises (excitatory).
What is an metabotropic receptor?
A post synaptic receptor which is linked to intracellular/metabolic messengers; muscarinic cholinergic, adrenergic depolarising or hyperpolarising (excite or inhibit)
Can autonomic preganglionic neurons inhibit postganglionic neurons?
No, preganglionic neurons can only excite, but postganglionic neurons can excite OR inhibit effectors.
Are organs ever innervated by both the parasympathetic and sympathetic nervous systems?
Yes, several organs and glands are, such as the heart, GI tract, bladder, genitals etc.
