Discussion about different types of neurotransmitters of human brain

1. Neurotransmitters
(How it works?)
By:
Pamela M. Veroy, RN, MAN

2. Is your brain this size?

3. ANATOMY & PHYSIOLOGY
NERVOUS SYSTEM (NS)
• CENTRAL NS
– BRAIN & SPINAL CORD
• PERIPHERAL NS
– CRANIAL & SPINAL NERVES
• AUTONOMIC
– SYMPATHETIC - THORACO- LUMBAR
– PARASYMPATHETIC – S2,3,4

4. ANATOMY & PHYSIOLOGY
BRAIN:
• CEREBRUM
• DIENCEPHALON
• BRAIN STEM
• CEREBELLUM

5. ANATOMY & PHYSIOLOGY
CEREBRUM
• HEMISPHERES
• LOBES
• CORPUS CALLOSUM
• BASAL GANGLIA
• FRONTAL
• PARIETAL
• TEMPORAL
• OCCIPITAL

6. ANATOMY & PHYSIOLOGY
FRONTAL LOBE:
• PERSONALITY, BEHAVIOR
• HIGHER INTELLECTUAL FUNCTIONING
• PRECENTRAL GYRUS: MOTOR FXN
• BROCA’S AREA – MOTOR SPEECH
WERNICKE’S AREA OF TEMPORAL: SENSORY SPEECH
PARIETAL LOBE:
POST CENTRAL GYRUS : GENERAL SENSATION
INTEGRATES SENSORY INFO
BROO---M

7. ANATOMY & PHYSIOLOGY
TEMPORAL LOBE
• HEARING, TASTE & SMELL
• WERNICKE’S AREA – SENSORY SPEECH
BROCA’S AREA OF FRONTAL LOBE – MOTOR SPEECH
OCCIPITAL LOBE
VISION
BASAL GANGLIA
REGULATE & INTEGRATE MOTOR ACTIVITY
PART OF EPS

8. ANATOMY & PHYSIOLOGY
DIENCEPHALON
• THALAMUS
• HYPOTHALAMUS
BRAINS STEM
MIDBRAIN, PONS, MEDULLA
NUCLEI OF CN’s - 12
VITAL CENTERS OF: REPIRATORY, VASOMOTOR & CARDIAC
FXNS
CEREBELLUM
MUSCLE TONE & EQUILIBRIUM
PRIMITIVE EMOTIONS: RAGE & FEAR
CONTROL CENTER FOR PITUITARY
REGULATION OF VITAL FXN : BP, SLEEP, FOOD INTAKE, BODY TEMP

9. ANATOMY & PHYSIOLOGY
SPINAL CORD
• GRAY MATER
– H SHAPED
– INTERIOR
• WHITE MATER
– EXTERIOR
• CENTER OF REFLEX
ACTIONS
• 31 SEGMENTS :
– 8 CERVICAL
– 12 THORACIC
– 5 LUMBAR
– 5 SACRAL
– 1 COCCYGEAL

10. ANATOMY & PHYSIOLOGY
MENINGES
• SEROUS MEMBRANE OF
CRANIOSPINAL CAVITY
• 3 LAYERS:
– DURA
– ARACHNOID
– PIA
-CS FLUID

11. ANATOMY & PHYSIOLOGY
NERVES
• FIBERS WHICH EXTEND
BEYOND CNS
• NEURON
-BASIC UNIT
REFLEX ARC
BASIC FXNAL UNIT OF N.S.
SENSORY/MOTOR
MIXED
PERIPHERAL

12. Neurotransmitters
• Approximately 100 billion brain cells form groups
of neurons, or nerve cells that are arranged in
networks.
• These neurons communicate information with
each other by sending electrochemical messages
from neuron to neuron, a process called
neurotransmission

13. • These electrochemical messages
pass from the dendrites
(projections from the cell body),
through the cell body, down the
axon (long, extended structures),
and across the gaps between cells
(synapse) to the dendrite of the
next neuron.
• In the nervous system, the
electrochemical cross the gaps or
synapse between neural cells by
way of special chemical messenger
called neurotransmitters.

14. • Neurotransmitters are the chemical substances
manufactured in the neuron that aid in the
transmission of information throughout the
body.
• They either excite or stimulate an action in the
cells (excitatory) or inhibit or stop an action
(inhibitory).

15. • These neurotransmitters fit into specific
receptor cells embedded in the membrane of
the dendrite, just like a certain key shape fits
into a lock.
• After neurotransmitters are released into the
synapse and relay the message to the
receptor cells, they are either transported
back from the synapse to the axon to be
stored for later used (reuptake) or are
metabolized and inactive by enzymes,
primarily monoamine oxidase (MAO) (Lewis
2000)

16. The Neurotransmitters

17. • Major transmitters
have been found to
play a role in
psychiatric illnesses
are well an actions
and side effects of
psychotropic drugs.
• Dopamine and
serotonin have
received the most
attention in terms
of the study and
treatment of
psychiatric
disorders (Tecott,
2000).

18. • These
neurotransmitters
are necessary in
just the right
proportions to
relay messages
across the
synapse.

19. • Studies are
beginning to show
that there is a
difference in the
amount of some
neurotransmitters
available in the brain
of persons with
certain mental
disorders compared
with persons with no
signs of mental
illness.

21. • The following is a discussion of the major
neurotransmitters that have been associated
with mental disorders.
Type of
transmitter
Mechanism
of action
Physiologic effects
Dopamine Excitatory Controls complex
movements, motivation,
cognition; regulates
emotional response
Norepinephrine
(noradrenaline)
Excitatory Changes in attention,
learning and memory,
sleep and wakefulness,
mood

22. Type of
transmitter
Mechanism of
action
Physiologic effects
Epinephrine
(Adrenaline)
Excitatory Fight-or-flight response
Serotonin Inhibitory Control of food intake, sleep
and wakefulness, temperature
regulation, pain control, sexual
behaviors, regulation of
motions
Histamine Neuromodulat
or
Alertness, control of gastric
secretions, cardiac stimulation,
peripheral allergic response
Acetylcholine Excitatory or
inhibitory
Sleep and wakefulness cycle;
signals muscles to become
alert

23. Type of
transmitter
Mechanism
of action
Physiologic effects
Neuropeptides Neuromodu
lators
Enhance, prolong, inhibit,
or limit the effects of
principal
neurotransmitters
Glutamate
Gamma-amino
butyric acid
(GABA)
Excitatory Neurotoxicity results if
levels are too high
Modulates other
neurotransmitters

24. • Histamine
• The role of histamine in
mental illness is under
investigation.
• It is involved in producing
peripheral allergic
responses, control of
gastric secretions, cardiac
stimulation, and alertness.
• Some psychotropic drugs
block histamine, resulting
in weight gain, sedation,
and hypotension.

25. • Acetylcholine
• Acetylcholine is a neurotransmitter found in the brain,
spinal cord, and peripheral nervous system,
particularly at the neuromuscular junction of skeletal
muscle.
• It can be excitatory or inhibitory. It is synthesized
from dietary choline found in red meat and
vegetables and has been found to affect the
sleep/wake cycle and signals muscles to become
active.
• Studies have shown that persons with Alzheimer’s
disease have a decreased number of acetylcholine-
secreting neurons
• Persons with myasthenia gravis (a muscular disorder
in which impulses fail to pass the myoneural junction,
causing muscle weakness) have a reduced number of
acetylcholine receptors.

26. • Gamma-amino butyric Acid (GABA)
• GABA, an amino acid, is the major inhibitory
neurotransmitter in the brain and has been found to
modulate other transmitter systems rather than
providing a direct
• Drugs that increase GABA function, such as
benzodiazepines, are used to treat anxiety and
induce sleep.
• Glutamate is an excitatory amino acid that at high
levels can have major neuro-toxic effects.
• Glutamate has been implicated in the brain damage
caused by stroke, hypoglycemia, sustained hypoxia
or ischemia, and some degenerative diseases such
as Huntington’s or Alzheimer’s disease.

27. Brain Imaging Technology
Procedure Imaging Method Results Duration
Computed
tomography(
CT) Magnetic
resonance
imaging
Serial X-rays of
brain
Radio waves
from brain
detected from
magnet
Structural
Image
Structural
Image
20-4
minutes
45 minutes
Position
emission
tomography
(PET)
Radioactive
tracer injected
into bloodstream
and monitored as
client perform
activities
Functional 2-3 hours

28. Procedure Imaging Method Results Duration
Single
photon
emission
computed
tomography
(SPECT)
Same as PET Functional 1-2 hours

29. Limitations of brain Imaging techniques
• The use of radioactive substances in PET and
SPECT limits the number of time as person can
undergo these tests.
• There is the risk that the client will have an
allergic reaction to the substances.
• Some clients may find receiving intravenous
does of radioactive material frightening or
unacceptable.
• Imaging equipment is expensive to purchase and
maintain, so availability can be limited. A PET
camera cost about $2.5 million; a SPECT camera
cost about $ 500,000.

30. • Some person cannot tolerate these
procedures because of fear or claustrophobia.
• Researchers are finding that many of the
changes that occur in disorders such as
schizophrenia are at the molecular and
chemical level and cannot be detected with
current imaging techniques.

31. • Find as
many as
you can
the
neurotrans
mitters in
the word
puzzle box.
• Clue- there
are 19.

32. Answers