Fundamentals of Drug Modification on Neurotransmission, Receptors in the ANS

FUNDAMENTALS
OF
PHARMACOLOGY
4BBY1040



Fundamentals of Drug
Modification on
Neurotransmission, Receptors in
the ANS

, LECTURE 6:

Neurotransmission and how neurotransmission may be modified by
drugs.
Neurotransmitters to know:
 Noradrenaline (NA) - sympathetic
terminals
 Acetylcholine (ACh) - parasympathetic
terminals, ganglia and Neuromuscular
junctions (NMJ)
 Dopamine (DA) - parts of the CNS
 Serotonin (5-HT) - parts of the CNS
 Nitric Oxide (NO) - odd places like
endothelium
Ganglia: a group or tissue with high
concentrations of neurons.

Sympathetic Nervous system: Emanates from Thoracolumbar segments of spinal
cord. Ganglions typically close to the spinal cord in the paravertebral chain.

Parasympathetic Nervous system: Craniosacral outflow, ganglia close or inside
target tissues. Cranial involved oculomotor, facial, vagal nerves. Sacral involves
nerve evigentes.

Areas of drug modification on neurotransmitter
Synthesis / Storage of NT
1. Stimulatory effects
a. Provide excess precursor (L-DOPA)
2. Inhibitory effects
a. Block precursor uptake
(hemicholinium)
b. Enzyme cascade (AMPT)
c. Storage (Reserphine)
Release of NT
3. Stimulation
a. Displaces NT
(amphetamine)
4. Inhibition
a. Depolarization (guanethide)
b. Ca uptake (conotoxin)
c. Vesicle fusion (botulinum)
d. Presynaptic receptor
(clodine)
Termination of neurotransmission
5. Inhibition, (will have stimulatory
effect)
a. Reuptake (cocaine)
b. Inhibit enzymatic
degradation (neostigmine)