SHS.302 Lec-9.ppt for dpt course in education

Dpt course lec pharmacology

1. Course Code 302
Resource Person DR. KHURRAM
PHARMACOLOGY

2. The nervous system controls all the major functions of the body. It
is divided into central and peripheral nervous systems. The
peripheral nervous system includes the somatic and
autonomic nervous systems which control voluntary and
involuntary functions respectively.
The ANS controls the vegetative functions of the body. These
include functions like circulation,
respiration, digestion and the maintenance of body temperature

3. Anatomical Classification
Nervous System
Central nervous
system
Brain Spinal Cord
Peripheral
nervous system
1. Cranial Nerves
2. Spinal Nerves
3. Nerve Ganglia

5. 2. Peripheral Nervous System
•Cranial Nerves
12 pairs
Originate in brain and leave the skull through
foramina.
•Spinal Nerves
31 pairs
Originate in spinal cord and leave it through
intervertebral foramina.

6. Spinal Cord
a)Cervical segment 8 pairs(C1-C8)
b)Thoracic segment 12 pairs(T1-T12)
c)Lumber segment 5 pairs(L1-L5)
d)Sacral segment 5 pairs(S1-S5)
e)Coccygeal segment 1 pair

7. .
The ANS is subdivided into two major sub-divisions; this
classification is based on both
anatomic and physiologic grounds; the two subdivisions are
sympathetic (thoracolumbar T1-L2/L3)) and
parasympathetic (craniosacral S2-S4,Cranial Nerves 3,7,9,10).
Autonomic nerves are actually composed of two neuron
systems, termed preganglionic and postganglionic, based on
anatomical location relative to the
ganglia. A preganglionic neuron has its cell body in the spinal cord
or brain

8. The sympathetic nervous system arises from the thoracic and
lumbar areas of the spinal cord
and the preganglionic fibers for the parasympathetic nervous
system arise from the cranial and sacral nerves. The
postganglionic neurons send their axons directly to the effector
organs(peripheral involuntary visceral organs).

9. Autonomic Nervous System
•ANS acts on smooth muscles & glands
-Controls & regulation of the heart, respiratory.
system, GI tract, bladder, eyes & glands
-Involuntary -person has little or no control
•Somatic -voluntary -person has control (skeletal
muscle)

11. Autonomic Nervous System
•Central Nervous System (CNS) -Brain and spinal cord
•Peripheral Nervous System (PNS) -Located outside the
brain & spinal cord
* Autonomic Nervous System (ANS) & the somatic
•The PNS receives stimuli from the CNS & initiates
responses to the stimuli after it’s interpreted by the brain

12. ANS
•ANS has 2 sets of neurons:
1.Afferent (sensory) -sends impulses to the CNS for
interpretation
2.Efferent -receives impulses (info.) from the brain &
transmits from the spinal cord to the effectororgan cells
-2 branches -sympathetic &
parasympathetic nervous system

13. In terms of function, the parasympathetic nervous system is
concerned primarily with
conservation and restoration of function.
In contrast, the sympathetic nervous system is concerned with the
expenditure of energy, i.e

14. ANS -Sympathetic nervous
system (Adrenergic)
•Sympathetic Nervous System (adrenergic)
Norepinephrine = neurotransmitter
-Drugs that mimic = adrenergic drugs,
sympathomimetics, or adrenomemetics
*Adrenergic agonists -Drugs initiate a
response
-Drugs that block = adrenergic blockers, sympatholytics
or adrenolytics

15. Receptors that respond to adrenergic nerve transmitter are
termed adrenergic receptors. These
receptors are subdivided into alpha and beta adrenoreceptor
types on the basis of both agonist
and antagonist selectivity. The receptors have subclasses
depending on drug selectivity. These
are alpha 1 and 2 and beta 1, 2 and 3.

16. ANS
•4 types of adrenergic receptor organ cells:
1. Alpha-1 = vasoconstriction of blood vessels
inc. blood return to heart, inc. circulation, inc. BP
2. Alpha-2 = inhibits release of norepinephrine
dec. in vasoconstriction, dec. BP
3. Beta-1 = inc. in heart rate & force of contraction
4. Beta-2 = relaxation of smooth muscle in bronchi, uterus,
peripheral blood vessels

18. ANS -Parasympathetic Nervous
System (Cholinergic)
•Parasympathetic or Cholinergic Nervous System
Acetylcholine = neurotransmitter
-Drugs that mimic = cholinergic drugs,
parasympathomimetics
Cholinergic agonists-initiates a response
-Drugs that block = anticholinergic,
parasympatholytics
Cholinergic antagonists-prevents a response

19. ANS
•Sympathomimetic
pathway
Norepinephrine
From adrenergic neuron
Inc. heart rate
Pupil dilation
Adrenergic (sympathomimetic)
agents
Fight or Flight
•Parasymathomimetic
pathway
Acetylcholine
From cholinergic neuron
Dec. heart rate
pupil constriction
Cholinergic
(parasympathomimetic
agents)

20. Adrenergicsand Adrenergic Blockers
•Drugs that Stimulate the sympathetic Nervous
System (adrenergics, adrenergic agonists,
sypathomimetics, or adrenomimetics)
•Mimic the sympathetic neruotransmitters
norepinephrine and epinephrine
•Act on one or more adrenergic receptor sites located
on the cells of smooth muscles -heart, bronchioles,
GI tract, bladder, eye
•4 main receptors (alpha-1, alpha-2, beta-1, beta-2)

21. Sympathomimetics/
Adrenomimetics
•Stimulate adrenergic receptors: 3 categories
1.Direct-acting = directly stimulates receptors
(epinephrine or norepinephrine)
2. Indirect-acting= stimulates release of norep. from
vesicles of adrenergic neuron,block the reuptake of
noradrenaline (amphetamine)
3. Mixed-acting (indirect & direct) = stimulates receptor
sites & release of norep. from adrenergic
neuron(Ephedrine)

22. Sympathomimetic Agents/
Adrenergics
•Action -Many of the adrenergic drugs stimulate
more than one of the adrenergic receptor sites
(alpha & Beta)
•Response= Inc. BP, pupil dilation, inc. HR, &
bronchodilation
•Use = Cardiac stimulation, bronchodilator,
decongestant
•Side effects = State of hyperactivity in body

23. Sympathomimetics/Adrenergics
•Albuterol-Beta-2 agonist
(bronchodilation)(Increases airflow to lungs)
Use -bronchospasm, asthma, bronchitis
SE –headache, dizziness, NVD , Sleep problems
Epinephrine-stimulates alpha & beta receptors(Acts
quickly to constrict Blood vessels ,broncodilation ,
helps to stop swelling on face)
Use -Severe allergic reaction(Anaphylaxis), cardiac
arrest
SE -nervousness, agitation(anxiety or nervous
excitement)

24. Adrenergic Agents
•Dopamine-alpha-1 & beta-1
stimulation(Increase contractility and Cardiac
output,Vasoconstriction alpha 1
effect,Increase blood flow to kidneys)
Use –Hypotension that occur when in shock
which may be caused by heart attack , trauma
and other serious conditions. It increases
cardiac output, improve perfusion to vital
organs