Now neurobiology quite easy

1. Kuvempu University
Department of Biotechnology
Jnana sahyadri
Shankaraghatta
Seminar on:
NEUROTRANSMITTERS AND NEUROPLASTICITY
Guided by:
Dr. Y.L .RAMACHANDRA
professor
Dept. of Biotechnology
Presented by:
BASAVARAJU KC
M.Sc. IInd semester
Dept. of Biotechnology

2. INTRODUCTION;
Neuroscience is the scientific study of the nervous system.
That deals with the anatomy, biochemistry, molecular biology, and
physiology of neurons and neural circuits.
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3. What the brain is made up of?
75% water
+
Consisting of a
minimum of
60% fat(myelin
sheath).
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4. A neuron is a nerve cell that is the basic building block of the
nervous system
NEURON;
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5. REFLEX ACTION AND REFLEX ARC;
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6. MECHANISM OF GENERATION AND CODUCTION OF NERVE IMPLUSE;
IN NON MYLINATED;
MYLINATED;
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saltatory conduction
( saltatory meaning
'jumping')

7. TRANSMISSION OF IMPULSES;
Chemical Synaptic Transmission.-NEUROTRANSMITTERS
The electrical signal cannot “jump” over that gap. Instead, at the point of synaptic
junction between two neurons, the electrical signal is “translated” into a chemical message
by the presynaptic neuron terminal
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8. How does a nerve stimulate a muscle to contract?
MYOSIN
MOTOR
NEURON
AND
muscle
fibers
MYOFIBER
Actin
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9. NEUROTRANSMITTERS;
Chemical substance that acts as the mediator for the transmission of nerve impulses from one neuron to
another neuron through synapse.
It a messenger of neurologic information from one cell to another.
Discovery of Neurotransmitters;
In 1921, an Austrian scientist named Otto Loewi discovered the first neurotransmitter
• Loewi hypothesized that electrical stimulation
of the vagus nerve released a chemical into the fluid of
chamber 1 that flowed into chamber 2.
• proved that the neurotransmition was chemical rather
than eletrical
Otto Loewi's Experiment
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10. WHAT BASICALY THIS CHEMICAL MESSANGERS
( NEUROTRANSMITTERS);
• The amino acid neurotransmitters
glutamate, GABA (γ-aminobutyric acid), and glycine. All of these
are amino acids
GABA is not an amino acid that's found in proteins.
• The biogenic amines( one or more amine groups );
dopamine, norepinephrine, epinephrine, serotonin,
• Acetylcholine Organic chemical
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11. A neurotransmitter’s effects depend on its
receptor;
• Excitatory neurotransmitters; -STIMULATE NEURONS
EX; Noradrenaline. dopamine, serotonin, glutamate,
• INHIBITORY neurotransmitters; SUPPRESS THE NEURONS
EX; GABA
EX; acetylcholine receptors
skeletal muscle cells - nicotinic acetylcholine
receptors.
heart muscle cells - muscarinic acetylcholine
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ROLE OF NEUROTRANSMITTERS IN THE BODY

13. Neuro plasticity ; the changing of the structure,
function, and organization of neurons in response to new
experiences
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14. NEUROPLASTICITY OF LEARNING AND MEMORY;
Where ,How, What in the form ours huge memory stored?
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15. A large amount of glutamate is
released the AMPA receptor
Increased influx of positive ions expels
magnesium from the NMDA channel
NMDA channel which now activates
allowing not only sodium but also
calcium into the cell
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•Small amount of glutamate is released and
bind
• NMDA pore is blacked by magnesium ions
•This is short term potential memory
The pre synaptic neuron is stimulated by When the pre synaptic neuron is stimulated
weak signal by strong or repeating signal
pre synaptic glutamatergic
neuron
LTP

16. when calcium into the cell ;
• calcium is the mediator of LTP memory
induction
HOW?
• calcium initiates signalling pathways that activate several protein kinase ,this kinase
enhance synaptic communication
phosphorylate the existing
AMPA receptors
Help to bring more AMPA receptors
from intracellular stores
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17. • Proteins are made and gene expression is activated to further
enhance the connection between the two neurons
• This include newly synthesized AMPA receptors and expression of
other protein that are involved in the growth of new dendrite spine
and synaptic connection
• Memories are stored as changes in synaptic connectivity
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18. Newly synthesized AMPA receptors and expression of other protein that are
involved in the growth of new dendrite spine and synaptic connection
Memories are stored as changes in synaptic connectivity
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19. APPLICATION;
1)ANTI-DEPRESENTS;
1) Selective serotonin reuptake inhibitors (SSRIs);
Class of drugs that are typically used as antidepressants in the treatment of major
depressive disorder and anxiety disorders.
+
A newer drug
fluoxetine (Prozac),
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20. • Dopamine a safe anti-angiogenic drug in cancer
treatment, study shows;( January 7, 2015,Ohio State
University Wexner Medical Center)
That dopamine is an inexpensive drug currently used to
treat heart, vascular and kidney disorders - can be safely used in
cancer treatment to stop (halt) the growth of blood vessels in
tumors (angiogenesis). Vascular endothelial growth
factor (VEGF)-signal protein
produced by cells that
stimulates the formation of
blood vessels.
Its help to bind the vegf and
inhibit the binding of its
receptors on blood vessels
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Anxiety disorders;
EXAMPLE DRUG IS
Benzodiazepines

22. ANASTHESIA;
The local anesthetics target open channels and prevent ion flow. they
block sodium channels more.
EX;
Lignocaine (USA: lidocaine): e.g. Remicaine®, Petercaine®
Bupivacaine: e.g. Macaine® Naropin®
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23. • Passiflora incarnata (Purple Passion flower) herb;
• Its most popular uses for treatment to insomnia and anxiety .
flavonoids the active ingredient of Passiflora.
• St. John's wort herbs;, Contains different Chemical
constituent Hyperforin and adhyperforin, they induce non-
competitive reuptake inhibition of monoamines
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24. CONCLUSION;
The ability of nervous system to organize complex
behaviours, learn and remember depends on
communication between vast number of neurons.
Communication mediated by neurotransmitter
They play an important role in control and coordination
of body.
Many neurological diseases and mental disorders are due
to improper functioning of neurotransmitters
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25. Neural plasticity specifically refers to
strengthening or weakening nerve connections
or adding new nerve cells. its highly helpful in
formation, storing and learning of memory
Neuroplasticity is changing of the structure,
function, and organization of neurons in
response to new experiences.
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26. References;
• Neurobiology,2nd edition by Garry G. Mathews
• Principle of Anatomy and Physiology,11th edition by
Gerard T Tortara
• Neurotransmitter-Acetylcholine in www.Britannica.com
• Alias medical video;
https://www.youtube.com/watch?v=4Hm08ksPtMo
• Text book of biology for first PUC
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