How is the excitation transmitted at the neuromuscular junction
Motorized end plate
The motorized end plate is the contact point between a nerve and a muscle cell. Here you will learn how it is structured and how the transmission of excitations works.
- Motorized end plate simply explainedin the text
- Motorized end plate structurein the text
- Neuromuscular synapse processesin the text
Motorized end plate simply explained
In order for you to be able to move the muscles in your leg, for example, your nerve cells (neurons) have to transmit electrical signals from the central nervous system (brain and spinal cord) to the muscle cells. To do this, the Nerve cells in contact with the muscle cells stand. You call the special junction between a neuron and a muscle cell motorized end plate or neuromuscular synapse.
In general, you refer to the contact points of a nerve cell with another cell as Synapses. They serve to transmit excitations (Action potentials) In the case of the motor endplate, a motor neuron transfers the excitation to a muscle cell and releases a so-called there Endplate potential (EPP).
Motorized end plate structure
The neuromuscular endplate is constructed in exactly the same way as a "normal" synapse. That means you can break it down into three sections:
- presynaptic membrane:corresponds to the synaptic terminal (presynaptic terminal) of the nerve cell; contains Vesicle(membrane-covered vesicles) with the messenger substance acetylcholine
- synaptic gap:Area between the two cells; Release of the messenger substance (= Neurotransmitters)
- postsynaptic membrane: corresponds to the membrane of the muscle cell; contains Receptors for acetylcholine in the membrane
The cell membranes involved are strongly folded. In this way, they increase the surfaces with which they are in contact. This allows the neuron to transmit the excitation better.
Neuromuscular synapse processes
Let's take a step-by-step look at which processes take place at the synapse and how the transmission of excitation works:
- First reached a Action potential the end button / soleplate of the nerve cell. By this you mean a deviation of the voltage from that in the resting state (resting potential). This leads to a Depolarization (Decrease in voltage).
- Then open Calcium ion channels. So approx2+Ions into the presynaptic cell.
- Thus the neurotransmitter is released Acetylcholine from the vesicles into the synaptic cleft. To do this, the vesicles fuse with the membrane. You call the process Exocytosis.
- After the transmitter has moved to the postsynaptic membrane, it can address specific - so-called nicotinic acetylcholine receptors - tie. You call the type of receptor a ionotropic. This means that it also forms an ion channel at the same time. The channel then opens through the binding of acetylcholine.
- The ion channel is unspecifically permeable to Cations (positive ions). This means that both sodium, calcium and potassium ions can pass through. The ions flow into the muscle cell and thereby depolarize the cell.
- A so-called end plate potential arises and spreads. After all, that solves one Muscle contraction out.
The neurotransmitter acetylcholine releases itself from its receptor after a while. A special enzyme, acetylcholinesterase, then breaks down the free acetylcholine in the synaptic gap. To do this, she splits it into acetate and choline. The molecules can then be taken up again by the presynapse and recycled. This means that the cell uses it to form new acetylcholine and repackage it in vesicles. Now a new transmission of excitation can begin.
- Which human sense is the most detailed
- Have you ever dated a psychopath
- How did LoopNet get the first traction
- What are the best Facebook sticker packs
- What are good websites for learning cocoa
- How did the Holy Roman Empire work
- In what month does Accenture issue letters of call?
- What is the diagnosis and treatment
- What does a slow metabolism mean
- Which videos are illegal to shoot
- Is the self-help industry overrated
- Will protein shakes harm you
- How can I buy back my shares
- How does an octa-core processor work
- What are you secretly jealous of?
- What igneous rocks do crystals have
- What is a depressed mood
- Is it wrong to use Rompler presets?
- Which trumpet tips beginners mostly ignore
- How important is physical appearance to narcissists
- How strong is the Discordcrypt encryption
- Will resumes ever become obsolete
- Which Hollywood actress is totally underestimated?
- Is SUNY a respected institution in Albany
- What should everyone know about himself?
- How do you see Baleno's car
- Why do I hate taking supplements?
- What is a circular knitting machine
- Who is an international lawyer
- Cats cry when they are sad
- Which is better Desk com or Zendesk
- How am I supposed to avoid being humiliated by friends?
- How much is 450mAh in the battery life