Question

How is the effect of a neurotransmitter different from that of a neuromodulator? Give an example of a neurotransmitter that is also a neuromodulator.  

Answer 1

NEUROTRANSMITTER	NEUROMODULATOR
A chemical substance released at the end of a nerve fiber by the arrival of the nerve impulse and by diffusing across the synapse or junction.Effect the transfer of the impulse to another nerve fiber , amuscle fiber	A substance other than a neurotransmitter released by a neuron and transmitted information to other neuron,altering their activities
Affect on one or two post synaptic targets at once	Affect on a group of postsynaptic targets
Affect directlyon their post synaptic target	indirectly affect on their post synaptic target via second messenger
Affect the adjascent post synaptic targets	Affect on targets,which are quite far away from the point of release
Degraded or taken up by the neuron rapidly	is not degraded rapidly or taken up by the neuron
produces a rapid effect which are last for a short time duration	producees a slow but long lasting effect
eg: serotonin, acetylcholine,dopamine,GABA,glycine	opiod peptides such as Enkephalins,Endorphins,dynorphins

Neuromodulators that act as a neurotransmitters are Dopamine , Acetyl choline, Nor epineprine, serotonin