السلام عليكم ورحمة الله وبركاته
إن شاء الله سوف أنقل لكم بعض تلخيصات الفارما لخريجى صيدلة والموضوع منقول للأمانة من مواقع أخرى نبدأ الآن باسم الله:
The preganglionic fibers
arise from the cranial and sacral areas of the spinal cord
synapse in ganglia near the effector organs
Function of the sympathetic system
Not essential for life
Has the property of adjusting in response to stressful situations such as
Effects of stimulation of the sympathetic devision
increase heart rate
increase blood pressure
mobilize energy stores in the body
increase blood flow from the skin to skeletal muscles and heart
diverting flow from the skin and internal organs
stimulation of the pupils and bronchioles
i.e : Fight &Flight response due to
Direct sympathetic response
Stimulation of adrenal medulla to release epinephrine and norepinephrine
Functions of the parasympathetic system
Essential for life
Maintain essential body functions
Usually acts to oppose or balance the actions of the sympathetic division
It is a dominant over the sympathetic division in rest & digest stimulation
Affect specific organs such as stomach and eye
I- dual innervation
Most organs in the body are innervated by both divisions
'ex : the heart has
a) vagal parasympathetic innervation which slows the rate of contraction
b) sympathetic innervation speeds contraction
c)the vagus is the predominant controlling factor for rate
II- Organs receiving only sympathetic
examples
Adrena medulla
Kidney
Pilomotor muscle
Sweat glands
Cholinergic and adrenergic neurotransmitters are the primarily chemical signals in the autonomic nervous system
The autonomic nerve fibers can be classified into 2 groups based on the chemical nature of the neurotransmitter released
Acetyl choline
Released from the preganglionic neurons in
both parasympathetic and sympathetic
in adrenal medulla
in neuromuscular junction
Norepinephrine & epinephrine
In sympathetic.it is released from the postganglionic neurons to the
effector organs
يتبع إن شاء الله
إن شاء الله سوف أنقل لكم بعض تلخيصات الفارما لخريجى صيدلة والموضوع منقول للأمانة من مواقع أخرى نبدأ الآن باسم الله:
The autonomic nervous sysyem
Anatomy
Anatomy
I-Efferent neurons
Carries nerve impulses from the CNS to the effector organs by way
of 2 types of efferent neurons
a) a preganglionic neuron
Its cell body located within the CNS
Emerge from the brain stem or the spinal cord
Make a synaptic connection in ganglia which act as arelay station between the preganglionic neuron and the postganglonic neuron
b) a postganglionic neuron
Its cell body originating in the ganglia
Terminates on effector organ such as
Smooth muscle of the viscera
Cardiac muscle
Exocrine glands
II- Afferent neurons
are important in the reflex regulation of this system
ex: sensing pressure in the carotid sinus and aortic arch and signaling the CNS to influence the efferent branch of the system to respond
Sympathetuc neurons
The preganglionic neurons of sympathetic system
Come from thoracic and lumber regions of the spinal cord
Synapse in 2 cord-like chains of ganglia that run parallel on each side of the spinal cord
Axons of the postganglionic neurons extend from these ganglia to glands & viscera
Special case : (The adrenal medulla) : acts like the sympathetic ganglia
a)receives preganglionic fibers
b)lacking axons
c) if stimulated,it secretes the hormone(epinephrine= adrenaline) + less amount of norepinephrine which influence other organs
Carries nerve impulses from the CNS to the effector organs by way
of 2 types of efferent neurons
a) a preganglionic neuron
Its cell body located within the CNS
Emerge from the brain stem or the spinal cord
Make a synaptic connection in ganglia which act as arelay station between the preganglionic neuron and the postganglonic neuron
b) a postganglionic neuron
Its cell body originating in the ganglia
Terminates on effector organ such as
Smooth muscle of the viscera
Cardiac muscle
Exocrine glands
II- Afferent neurons
are important in the reflex regulation of this system
ex: sensing pressure in the carotid sinus and aortic arch and signaling the CNS to influence the efferent branch of the system to respond
Sympathetuc neurons
The preganglionic neurons of sympathetic system
Come from thoracic and lumber regions of the spinal cord
Synapse in 2 cord-like chains of ganglia that run parallel on each side of the spinal cord
Axons of the postganglionic neurons extend from these ganglia to glands & viscera
Special case : (The adrenal medulla) : acts like the sympathetic ganglia
a)receives preganglionic fibers
b)lacking axons
c) if stimulated,it secretes the hormone(epinephrine= adrenaline) + less amount of norepinephrine which influence other organs
Parasympathetic neurons
The preganglionic fibers
arise from the cranial and sacral areas of the spinal cord
synapse in ganglia near the effector organs
In both : postganglionic fibers extend from the ganglia to the effector organs
Function of the sympathetic system
Not essential for life
Has the property of adjusting in response to stressful situations such as
trauma - fear - hypoglycemia - cold - exercise
Effects of stimulation of the sympathetic devision
increase heart rate
increase blood pressure
mobilize energy stores in the body
increase blood flow from the skin to skeletal muscles and heart
diverting flow from the skin and internal organs
stimulation of the pupils and bronchioles
i.e : Fight &Flight response due to
Direct sympathetic response
Stimulation of adrenal medulla to release epinephrine and norepinephrine
Functions of the parasympathetic system
Essential for life
Maintain essential body functions
Usually acts to oppose or balance the actions of the sympathetic division
It is a dominant over the sympathetic division in rest & digest stimulation
Affect specific organs such as stomach and eye
Innervation by the autonomic nervous system
I- dual innervation
Most organs in the body are innervated by both divisions
'ex : the heart has
a) vagal parasympathetic innervation which slows the rate of contraction
b) sympathetic innervation speeds contraction
c)the vagus is the predominant controlling factor for rate
II- Organs receiving only sympathetic
examples
Adrena medulla
Kidney
Pilomotor muscle
Sweat glands
N.B :the control of blood pressure is also mainly a sympathetic activity
Neurotransmitters
Neurotransmitters
Cholinergic and adrenergic neurotransmitters are the primarily chemical signals in the autonomic nervous system
The autonomic nerve fibers can be classified into 2 groups based on the chemical nature of the neurotransmitter released
Acetyl choline
Released from the preganglionic neurons in
both parasympathetic and sympathetic
in adrenal medulla
in neuromuscular junction
Norepinephrine & epinephrine
In sympathetic.it is released from the postganglionic neurons to the
effector organs
يتبع إن شاء الله
تعليق