Textbook Question
The anatomical region of a multipolar neuron where the AP is initiated is the
a. Soma
b. Dendrites
c. Axon's initial segment
d. Axon terminals
798
views
1
rank
11. Nervous Tissue and Nervous System
Change in Membrane Potential
2:04 minutesProblem 22
Textbook Question
When admitted to the emergency room, Sean was holding his right hand, which had a deep puncture hole in its palm. He explained that he had fallen on a nail while exploring a barn. Sean was given an antitetanus shot to prevent neural complications. Tetanus bacteria fester in deep, dark wounds, but how do their toxins travel in neural tissue?
Verified step by step guidance1
Understand the nature of tetanus: Tetanus is caused by the bacterium *Clostridium tetani*, which produces a toxin called tetanospasmin. This toxin affects the nervous system and can lead to muscle spasms and rigidity.
Learn how tetanospasmin enters the nervous system: The toxin is released by the bacteria at the site of infection and binds to peripheral nerve endings. It is then taken up by the neurons through endocytosis.
Trace the toxin's path: Once inside the neuron, tetanospasmin travels retrogradely (backward) along the axon toward the spinal cord and brainstem. This process is facilitated by motor proteins that move along microtubules within the neuron.
Understand the mechanism of action: In the central nervous system, tetanospasmin blocks the release of inhibitory neurotransmitters, such as gamma-aminobutyric acid (GABA) and glycine, at synapses. This leads to unregulated excitation of motor neurons, causing muscle spasms and rigidity.
Recognize the importance of the antitetanus shot: The antitetanus shot contains tetanus toxoid, which stimulates the immune system to produce antibodies against tetanospasmin. This prevents the toxin from binding to neurons and causing neural complications.
Verified video answer for a similar problem:This video solution was recommended by our tutors as helpful for the problem above
Video duration:
2mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Tetanus Pathophysiology
Tetanus is caused by the bacterium Clostridium tetani, which produces a potent neurotoxin called tetanospasmin. This toxin interferes with normal nerve signaling, leading to muscle stiffness and spasms. Understanding how this bacterium thrives in anaerobic conditions, such as deep puncture wounds, is crucial for grasping the risks associated with such injuries.
Neural Tissue and Toxin Transport
Neural tissue is composed of neurons and glial cells, which facilitate communication within the nervous system. Tetanospasmin can travel retrogradely along axons, moving from the site of injury to the central nervous system. This transport mechanism is essential for understanding how the toxin affects motor neurons and leads to the characteristic symptoms of tetanus.
Recommended video:
02:37
Active Transport
Antitoxin Administration
Antitoxin therapy, such as the administration of tetanus immunoglobulin, is critical in preventing the effects of tetanospasmin after exposure. This treatment neutralizes the toxin before it can bind to nerve endings. Understanding the timing and effectiveness of antitoxin administration is vital for managing potential tetanus cases and preventing severe complications.
3:31mWatch next
Master Change in Membrane Potential with a bite sized video explanation from Bruce Bryan
Start learningRelated Videos
Related Practice