Exam 3: Autonomic Nervous System Flashcards
Autonomic System
- System of nerves mediating INVOLUNTARY actions
- Regulated body organ activity
- Maintains normal internal functions
- Allows for varied nervous system responses in times of stress and rest
What is the Autonomic Nervous system divided into?
Sympatheic
Parasympathetic
Includes processes perciveved or controlled consiously
Somatic Nervous System
Includes processes regulated below consious level
Autonomic Nervous System
Visceral Sensory
Portion of the Autonomic Nervous System:
detects stimuli from blood vessesl and interal organs
Somatic Sensory
Portion of the SNS:
Detects stiuli from special senses, skin, and proprioreceptors also sends infromation to CNS
Autonomic Motor
Portion of the ANS:
transmits nerve signals to cardiac muscle, smooth muscle, and glands
Somatic Motor
Portion of the SNS:
transmits nerve signals from CNS to control skeletal muscles
Anatomy of ANS:
2 Neuron System
Preganglionic neuron
Postganglionic neuron
Preganglionic
Cell body in the CNS and axon extends to a ganglion
Postganglionic Neuron
Cell body in ganglion and axon extends to an effector
What characterizes the sympathetic division of the ANS?
Fight of Flight
What characterizes the parasympathetic division of the ANS?
Rest and Digest
- Preganglionic neuron in brainstem or S2-S4 spinal cord
- Ganglionci Neuron innervating muscles or glands
Parasympathetic Division of ANS
- Preganglionic neuron in lateral horns of T1-L2
- Ganglionic neuron innervating muscels or glands
Sympathetic Division of ANS
Termed craniosacral divison
Parasympathetic Division of ANS
Termed thoracolumbar division
Sympathetic Division of ANS
Sympathetic Division:
Axon length
1st motor:
2nd motor:
1st motor: short axon
2nd motor:long axon
Sympathetic Division
2 types of sympathetic ganglia:
Sympathetic Trunk (Vertebral Chain) Ganglia
Collateral (prevertebral) Ganglia
Preveretebral (Collateral) ganglia
Celiac
Superior Mesenteric
Inferior Mesenteric
Aorticorenal
Renal
What 4 ways can the postganglionic neurons leave the sympathetic trunk?
- Spinal nerves
- Sympathetic nerves
- Splanchnic nerves
- Adrenal medulla pathway
Parasympathetic Division
Axon Length
1st Motor:
2nd Motor:
1st Motor:Long
2nd Motor:Short
Has many collaterals- up to 20
Sympathetic Division
Has few collaterals- 4 to 5
Parasympathetic division
True or False
The terminal ganglia are usually within the effector in the parasympathetic division.
True
Parasympathetic Ganglia
The cranial outflow has 4 pairs of ganglia:
- Ciliary Ganglia: III (Occulomotor)
- Pterygopalatine Ganglia: VII (Facial)
- Submandibular Ganglia: VII (Facial)
- Otic Ganglia: IX (Glossopharyngeal)
X (Vagus) nerve carries nearly % of the total craniosacral flow
80
Autonomic Plexuses
The 7 types
- Cardiac Plexus
- Pulmonary Plexus
- Celiac (Solar) Plexus
- Superior Mesenteric Plexus
- Inferior Mesenteric Plexus
- Hypogastric Plexus
- Renal Plexus
Autonomic Plexuses
A network of sympathetic and parasympathetic axons
Cardiac Plexus
Heart
Pulmonary Plexus
The Bronchial tree
Celiac Plexus
Largest
Supplies the stomach, spleen, pancreas, liver, gallbladder, and adrenal medullae
Superior Mesenteric Plexus
Small intestin and proximal colon
Inferior Mesenteric Plexus
Distal Colon and rectum
Hypogastric Plexus
Urinary bladder and genital organs
Renal Plexus
Kidneys and ureters
Neurotransmitters
- Acetylcholine (ACh) and Norepinephrine (NE)
- Bind to specific receptors on postsynaptic cell
- Cause stimulation or inhibition; depending on receptor
Cholinergic Neurons release
acetylcholine (ACh)
Cholinergic Neurons include:
1.
2.
3.
- All sympathetic and parasympathetic preganglionic neurons
- Sympathetic postganglionic neurons that innervate most sweat glands
- All parasympathetic postganglionic neurons
Cholinergic Receptors
Bind acetylcholine and are found on the post-synaptic cell
Two types of Cholinergic Receptors
Nicotine Recptors
Muscarinic Receptors
Nicotine Receptors
Sympathetic and Parasympathetic postganglionic neurons
Nicotine mimics the action of ACh when bound to these receptors
Muscarinic Receptors
In PM of effectors innervated by parasympathetic postganglionic neurons
In Chromaffin cells of adrenal medullae
Muscarine mimics the effects of ACh when bound to these receptors
Different subtypes have different responses (excitation/inhibition)
Andrenergic Neurons
Release norepinephrin
Most sympathetic postganglionic neurons are andrenergic
Adrenergic Receptors
2 Types of receptors on postsynaptic cell:
Alpha Receptors- 2 subtypes
Beta Receptors- 3 subtypes
Alpha 1 and Beta 1
Excitation in effectors
Alpha 2 and Beta 2
Inhibition of effectors
Beta 3
Found in BAT (Brown Adipose Tissue): found in babies
Autonomic tone
A balance between the sympathetic and parasympathetic activity
Regulated by the hypothalamus
Sympathetic Responses
As Stress increases what happens?
- Increased production of ATP
- Dilation of pupils
- Increased heart rate and blood pressure
- Dialation of airways
- Constriction of blood vessels that supply the kidneys and gastrointestinal tract
- increased blood supply to the skeletal muscles, cardiac muscle, liver and adipose tissue
- increased glycogenolysis Increased blood glucose
- Increased lipolysis
Parasympathetic Responses
- Used to conserve energy and return body to homeostasis
- increased digestive and urinary function
- decreased body functions that support physical activity
Cholinergic receptors bind to
Acetylcholine
Norepinephrine is released from which type of neuron?
Cholinergeric
The connective tissue layer that separates individual axons from one another is called the
Endoneurium
How many cervial spinal nerves are there?
8