Autonomic Pharmacology Flashcards
How does the nervous system exert its effects. By;
- the rapid transmission of electrical impulses over nerve fibers that terminate at effector cells,
- which specifically respond to the release of neuromediator substances.
The nervous system is divided into two name em
Central nervous system and peripheral nervous system
The peripheral system is divided into two name em and explain em
Efferent division and afferent division
(Motor)Efferent- sends impulses away from the CNS to other parts of the body
(Sensory )Afferent- sends impulses to the CNS
Division of the efferent with examples of each
Autonomic and somatic nervous system
Example of autonomic motor nerves- nerves attached to these smooth and cardiac muscle , glands
Example of somatic motor nerves- nerves attached to the skeletal muscles
Division of the Autonomic nervous system
Enteric , parasympathetic and sympathetic
Which areas in the brain are extremely important in the control of the Autonomic nervous system or ANS
Medulla oblongata- Involved in the integration of cardiovascular reflexes and blood pressure control
•Hypothalamus - is the principal integrative Centre for the entire ANS
Receptors detect changes in the body or the body’s environments then send the changes thru afferent arc to the sensory nervous system to the Central nervous system then the brain issues instructions through the efferent arc to the motor nervous system and to the effector organs . True or false
True
Explain the sympathetic nervous system
mobilizes the body during extreme situations
•the “fight-or-flight” system
•Involves E activities – exercise, excitement, emergency, and embarrassment
•Heart rate increases, and breathing is rapid and deep
•The skin is cold and sweaty, and the pupils dilate
When the pupils dilate in the sympathetic nervous system, what occurs
It causes the eye to see far and not near objects
Which part of the nervous system performs maintenance activities and conserves the body’s energy
Parasympathetic
Which part of the nervous system involves the D activities, exampleA defecation, digestion, diuresis
Parasympathetic
In which nervous system type are Blood pressure, heart rate, and respiratory rates low
,Gastrointestinal tract activity is high
And The skin is warm and the pupils are constricted
Parasympathetic
Both the para and sympa are two opposing systems which counterbalance each other’s activity. True or false
True
Name one example of how para and sympa oppose each other
When you’re angry, sympa is working so you don’t even feel hungry but when you’re not angry anymore you start to feel very hungry if you’ve not eaten this occurs due to the para
Which nervous system uses both para and sympa and functions independently of the CNS
Enteric nervous system
List four functions of the enteric system
collection of nerve fibers that innervate the
•gastrointestinal (GI) tract,
•pancreas,
•gallbladder, and
•it constitutes the “brain of the gut.”
•It controls motility, exocrine and endocrine secretions, and microcirculation of the GI tract.
Neurotransmitters are secreted and act on the effector organs or on another close neuron . True or false
True
Neurons with Myelin sheaths have their impulses transmitted faster than neurons without myelin sheaths. True or false
True
Somatic nervous system secreted which neurotransmitter to act on skeletal muscles
Acetylcholine
Somatic nervous system neurons have no ganglion or post ganglionic neuron. True or false
True
What is a ganglion
A place where neurons synapse or meet
The preganglionic neurons is closer to the spinal cord and closer to the ganglion true or false
True
In the sympathetic nervous system, the preganglion is shorter than the post ganglion true or false
True
For the para, the pre is very long and the post ganglion is short. True or false
True
Instead of a ganglion, there is adrenal medulla. Acetylcholine is produced by the first neuron and it sends impulses to the adrenal medulla to produce epinephrine and norepinephrine. True or false
True
What are the two ways sympathetic nervous system sends impulses to its effector organs
- Preganglionic neurons releases or secretes acetylcholine and this sends signal to the post ganglion to produce norepinephrine to work on effector organs(smooth muscles example what happens in a blood vessel)
- Neuron releases acetylcholine which makes the adrenal medulla to produce epinephrine and norepinephrine to be sent through blood vessels to the glands
In the parasympathetic- both post and pre secrete acetylcholine while in the sympa, pre secreted Acetylcholine ad post secretes epinephrine and norepinephrine. True or false
True
In the somatic nervous system- there are no ganglion whether pre or post true or false
True
Name four differences between para and sympa
Sympathetic
Origin of fibers is in the Thoracolumbar region of the spinal cord
Short preganglionic and long postganglionic
Ganglia are Close to the spinal cord
Neurotransmitter is acetylcholine and epinephrine and norepinephrine
Parasympathetic
Origin of fibers is in the Brain and sacral spinal cord
Long preganglionic and short postganglionic
Ganglia are In the visceral effector organs
Neurotransmitter is Acetylcholine
In sympa Preganglionic neurons synapse with many postganglionic neurons but in para
Preganglionic neurons synapse with few post- ganglionic neurons
Why
Cuz sympa, the pre neurons is shorter than the post neurons so there are more post. This is also why when receptors pick up changes in the sympa, more than one action can occur at the same time. You heart will beat faster at the same time you’ll be running very fast at the same time your eyes will be dilated.
The post is more so
More of the neurotransmitter is released to work on effector organs
But in para, actions occur one at a time because the post is lesser than the pre.
Heart has sympa and para innervation true or false
True
Alpha and beta recptors on the heart are for the sympa
And muscarinic receptor on the heart for the para
True or false
True
Beta one receptor increases the rate and force on contraction of the heart when what happens
When the beta 1 receptor is Activated by norepinephrine .
This increases cardiac output
Blood vessels have which receptors on them
Alpha 1 and beta 2 receptors from the sympathetic
When alpha is stimulated- there is vasoconstriction
When beta is inhibited- there is vasodilation
Radial muscle of the iris has a sympa innervation which causes what to the pupil
Dilation of the pupil
Sphincter muscle is innervated by the para muscarinic receptors which cause what to the pupil
Constriction
Vasoconstriction increases total peripheral resistance true or false
True
What two things cause an increase in bp
Cardiac output and total peripheral resistance
In sympa, saliva is thick and scanty while in para, saliva is watery and profuse true or false
True
Which system causes the relaxation and constriction of the bronchioles
Relaxation- sympathetic causes by beta 2 receptors
Constriction- para
In para, you get an erection due to the excitation of the muscarinic receptors
In sympa you get an ejaculation due to the alpha receptors excitation. True or false
True
Name some ways organs are innervated
Organs which receive both innervation from the para and sympa, the effects of the 2 divisions are usually opposed or antagonistic
Example the heart, bronchioles, GI tract and bladder
Even tho some organs have innervation from both organs, some organs are dominated by the sympa while others are dominated by the para.
Example- GI is innervated by both para and sympa but para dominates
Urinary bladder and salivary gland( para dominated)
Veins and sweat glands( sympa dominates)
Some organs receive two innervation from the sympa and para but the effects are complimentary
Example- salivary glands
Sympa makes saliva thick and not much but para makes saliva watery and more
So when you’re hungry the para works but when you’re anxious your saliva becomes thick even tho both make you produce saliva
Some organs have only one innervation- so they are regulated by increasing or decreasing activity of the nerves that innervated them. Example- 1.sweat glands ( it is under the sympa but is not norepinephrine that causes the sweat glands . It is the acetylcholine that is released . 2. Blood vessels
In some organs the control of function is regulated by opposing branches of the ANS but each branch exerts its activity on different cells.
•pupil
When one is under the para- the circular muscle constricts thereby pulling the radial muscle causing the pupil to be constricted true or false
But sympa- radial contracts and pulls circular muscle making pupil dilate for organ true or falseinnervation where there are opposing effects but each branch affects its own activity
True true
Name three interactions of the autonomic system
Interactions of the Autonomic Divisions
•Most visceral organs are innervated by both sympathetic and parasympathetic fibers
- This results in dynamic antagonisms that precisely control visceral activity
- Sympathetic fibers increase heart and respiratory rates, and inhibit digestion and elimination
- Parasympathetic fibers decrease heart and respiratory rates, and allow for digestion and the discarding of wastes
Which division of the nervous controls controls blood pressure and keeps the blood vessels in a continual state of partial constriction
Sympa
Which drugs are used to treat hypertension
•Alpha-blocker drugs interfere with vasomotor fibers and are used to treat hypertension
Importance of sympa tone or vasomotor tone
Constricts blood vessels and causes blood pressure to rise as needed
•Prompts vessels to dilate if blood pressure is to be decreased
Drugs that block para responses do what
ncrease heart rate and cause fecal and urinary retention
Sympa division overrides para during stress and fight or flight and para overrides sympa during relaxation true or false
True
Which division of the nervous system controls the activity of the adrenal medulla, sweat glands, arrector pili muscles, kidneys, and most blood vessels and
•Thermoregulatory responses to heat
•Release of renin from the kidneys
•Metabolic effects
Sympa
Mixture of semen and sperm triggers sympa tone to trigger man to ejaculate. True or false
True
Name the four events that are involved in neurochemical transmission
axonal conduction
- synthesis and release of neurotransmitter
- receptor events
- catabolism of the neurotransmitter
Explain axonal conduction and depolarization
When a neuron is there it is at a resting stage and is stable. As soon as there is an impulse and it exceeds the threshold there is an opening of a sodium channel or gate and it enters into the neuron and becomes positively charged and depolarization occurs. Depolarization means action potential is enough to activate a neuron.
There is axonal conduction due to action potentials
When neurochemicals are produced and they are in the vesicles and are at the terminal end of the neuron and is waiting to be released, what happens
It needs action potential before anything can occur. Depolarization causes the extra cellular part of the nerve to be negative and the intracellular part to be positive due to the movement of Na+ into the neuron this causes the influx of calcium. Calcium ion Ca2+destabilizes the vesicles . Vesicles moves and fuses with the nerve terminal membrane leading to exocytosis and the neurotransmitter is released and move to the effector tissue by diffusion.
Neurons communicate to each other through neurotransmitter and communicate within themselves through action potentials, depolarization . True or false
True