No brain no gain (NBE-E4210, week 4)
This week we were introduced to neurotransmitter systems. The lecture started with a warm up research example, where experimental rats learned to drink alcohol. This example was an interesting way to learn that alcohol stimulates the release of the natural morphine of body, resulting in good feeling. We have all done our bachelor’s minor in bioinformation technology, so neurotransmitters were familiar subject to us. However, we learned new information about neurotransmitters and deepened our understanding in this topic during the lecture. The background information of this topic helped us to remember all the information we had before learned.
Neurotransmitters are chemicals that transmist impulses from one neuron to another. The released neurotransmitters attach to the receptors on neuron, sending the signal forward, and later the neurotransmitters are returned to the initial neuron. During the lecture, we were shown an interesting video about depression. We learned that the cause of depression is believed to be the depletion of the neurotransmitters. A medical way to cure depression is introduced in the video. With the help of antidepressant drugs, neurotransmitters can be blocked from returning to the initial neuron, thus increasing the amount of available neurotransmitters.
Excitotoxicity was a new concept for us. So far, the importance of calsium have been emphasized in our previous courses. However, the overactivity of neuron caused by excess intracellular calsium can surprisingly kill the neuron. This kind of calsium influx is be caused by depolarized membrane potential due to failure in glucose and oxygen delivery to neuron. We learned new kind of receptors called nicotinic ACh (acetylcholine) and muscarinic ACh reseptors. Binding of ACh to nicotinic receptor opens a non-selective cation channel and the net effect is depolarization. ACh binding to muscarinic receptor is due to second-messenger signaling. The net effect is depolarization or hyperpolarization.
All in all, the lecture consists of complicated yet fascinating topics. The lecture helped us to understand neurons even more. Neuroransmitters are important chemicals for a functional neurous system. This lecture was the first part discussing the neurotransmitters and we are looking forward to the next part!