It is been a great journey and newer exercises which makes the contest more and more interesting. As we have discussed many facts about neuroscience from the first month lets get back to the core of neurotransmission and the basics of neurotransmitters.
Let me review the facts about neuron and the importance of neuron in few lines before getting into the basics of neurotransmitters.
Why neuron is important???????????
To explain in very simple language .........about neuron...........language is nothing but the media for communication through which we communicate and share information between us........so there is a need of a media......to communicate...to transform information's.......
Language is media between people........
What about the communication within individual..........
The communication between our body cells is happening through neuron and neurotransmitters are the messengers........
Neuron is a specialized cell which is designed to transmit information to other nerve cells, gland cells or muscle.
Neurons consist of cell body which produces neurotransmitters.......
[1,2]Neurotransmitters are endogenous chemicals which transmit signals from a neuron to a target cell across the synapse. Neurotransmitters are packaged into synaptic vesicles that cluster beneath the membrane on the presynaptic side of a synapse, and are released into the synaptic cleft where they bind to receptors in the membrane on the postsynaptic side of the synapse.
Criteria for a neurotransmitter:
- It should be produced & released from neuron.
- It should be a precursor/ synthesise enzyme in the presynaptic neuron.
- It should be in the pre synaptic neuron.
- Sufficient amount should be available for the postsynaptic neuron.
- It should bind to the postsynaptic receptors and shows biological effect
- It must be inactivated.
Types of neurotransmitters:
1) Excitatory- It is responsible for the conduction of impulse from pre to post synaptic neurons resulting in the opening of sodium channels & the influx of sodium ions from ECF. This depolarization is called EPSP (EXICTATORY POST SYNAPTIC POTENTIAL)
2) Inhibitory- It inhibits the conduction of impulse from pre to post synaptic neurons causes opening of potassium channels and efflux of potassium ions. This hyperpolarized state is called IPSP (INHIBITORY POST SYNAPTIC POTENTIAL).
Transport & release:
1) Destroyed /disintegrated by specific enzymes.
2) Engulfed & removed by astrocytes.
3) Removed by reuptake process.
Various neurotransmitters are as follows:
Both E & I
Both E & I
Along with this some neuropeptide neurotransmitters are also present, they are Corticotropin, substance, vasopressin, angiotensin, bradykinin, somatostatin, betaendorphin, atrial neuritic peptide, brain neuritic peptide.
Once there is a clear understanding of neurotransmitters in the brain and the drugs action on these may give clear solution to solve many problems (diseases).
This blog does not contain any plagiarized material
1) http://www.minddisorders.com/Kau-Nu/Neurotransmitters.html (Accessed on 21-06-10)
2) http://www.benbest.com/science/anatmind/anatmd10.html (Accessed on 16-06-10)
3) http://www.humanillnesses.com/original/images/hdc_0001_0003_0_img0257.jpg (Accessed on 22-06-10)