Explain Fate of the Neurotransmitter
Postsynaptic membranes bind the neurotransmitters by an active process. The chemicals keep moving in and out of the membrane. The synapse takes care not to have a continuous indefinite action. This is brought about by enzyme degradation, re- uptake mechanisms, recycling mechanisms etc. To illustrate, acetylcholine is removed by enzymatic hydrolysis from post synaptic membrane while nor-adrenaline is removed from the synaptic cleft by catechol-o-methyl transferase. It is further partly up-taken, partly recycled and inactivated by monoamine oxidase. Neurotransmitters therefore, cross the synapse enabling impulse transmission to an adjacent neuron. Once in the synapse, they are active for only a short time - between 0.5 and 1 millisecond. Enzymes in the synapse inactivate neurotransmitters, which are either taken back into the axon (reuptake) and transported back to the neuron for re-usage or destroyed. Next, having studied about the mechanism of transmission.