2. Why should there be drugs to act
on CNS…
The answer is simple;
In order to repair or
modify functions
of the CNS
3. Different states of the brain
Death
Convulsions
Excitation
Normal operating brain
Slight loss of sensation
Total loss of sensation
Death
4. Death
Anticonvulsants
Convulsions Anaesthetics
Preanaesthetics
Tranquilizers
Excitation
Normal operating brain (awake)
Slight loss of sensation
CNS stimulants Total loss of sensation
Anaesthesia antagonists
Death
5. Mechanisms of action
(on the synapse)
Action potential
Switch on Switch off
Speed up Modify slow down
6. Key players at the synapse
Neurotransmitter + Receptor
They can either be inhibitory or excitatory
In. N’trans + In. Rec. = (Reduced Activity)
Exc.N’trans + Exc.Rec = (Increased activity)
7. Common natural neurotransmitters in the brain
Glutamate (glutamic
Excitatory
Acid)
GABA Inhibitory
Dopamine Inhibitory
Acetylcholine Excitatory
Excitatory
Aspartic acid
Serotonin Inhibitory
Glycine Inhibitory
Norepinephrine Mostly Excitatory
8. Modification of the action potential
How does it occur???
Increase conc. of excitatory neurotransmitter
Assist stimulation of excitatory receptor
Switch on
Speed up
Decrease conc. of inhibitory neurotransmitter
Inhibit stimulation of inhibitory receptor
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48. Cyclohexamines
They include
Ketamine
Phencyclidine
Tiletamine
Telazol is a combination of tiletamine
and zolazepam
They produce what is referred to as
Dissociative Anaesthesia
49.
50. Etomidate
This is a sedative hypnotic
nonbarbiturate drug, of ultrashort
duration
52. CNS Stimulants
These are used for stimulation of some brain
centers like respiratory center.
They are also used for;
To counteract lethargy and fatigue
To reduce sleepiness.
To decrease appetite and promote weight loss,
as well as to treat obesity.
To improve concentration especially for those
with attentional disorders such as ADHD.
Occasionallyused to treat clinical depression.
