2. Neurotransmitter
Receptor – Binding site and ion channel same or different protein
Metabotropic Ionotropic
1. Ionotropic receptor
it contain both on same protein
Excitatory NT------EPSP----open cation channel ----- Depolarisation
Inhibitory NT ------IPSP---open Cl- channel------Repolarisation
3. • ii. Metabotropic Receptors
receptor is coupled with channel by a membrane protein Gprotein.
Directly open ion channel
Indirectly by secondary messenger,
Inhibitory NT ---K+ channel ----hyperpolarisation
• Neurotransmitter
1. Small molecule neuro
2. Neuropeptides
EPSPIonotropic
receptor
ACh
IPSPMetabotropic ReceptorsACh
4. 1. Small molecule neurotransmitter
a. Acetylcholine– Acetylcholine esterase
b. Aminoacid-
Glutamate & aspartate – ionotropic receptor – K channel
GABA & Glycine- Cl channel
c. Biogenic amine- Epinephrine, norepinephrine, dopamine and serotonin
Catecholamine ------- COMT&MAO
d. ATP & other purine
e. Nitric oxide
f. Carbon monoxide
ii. Neuropeptides
Opioid peptides- enkephalins, endorphins and dynorphins
Substance P
