Question

Term for sudden, irrepressible shock-like contraction of a muscle triggered by an event in CNS?

Answer 1

The term that describes a sudden, shock-like muscle contraction triggered by the CNS is called a spasm or convulsion. Such contractions can impede breathing if they involve the chest muscles and are caused by excessive stimulation from neurotransmitters like acetylcholine at the neuromuscular junction.

Step-by-step explanation:

Shock-like contraction of a muscle triggered by an event in the Central Nervous System (CNS), is most commonly referred to as a spasm or convulsion. This can occur from a wide range of causes, including electrical shock, but in the context of the CNS, it may be the result of various issues such as metabolic imbalances, neurogenic shock, or even an anaphylactic reaction resulting in spastic muscle contractions.

Such involuntary contractions can be severe and may lead to conditions where the onset of sustained muscular contraction is so strong that one cannot let go for the duration of the shock. In extreme cases, if the contraction involves the chest muscles, it may disrupt breathing, which is an emergency situation.

The contraction process begins when a motor neuron transmits a signal to a muscle fiber to initiate a muscle contraction, following the release of neurotransmitter acetylcholine at a neuromuscular junction. If this process becomes uncontrolled or excessive due to a shock-like event, it may result in prolonged and intense muscle contractions.

Answer 2

The sudden, irrepressible shock-like contraction of a muscle triggered by an event in the CNS is known as a spasm or convulsion. The mechanism involves neurotransmitter ACh release and receptor binding at the neuromuscular junction, resulting in muscle depolarization and contraction. Conditions like hypertonia or hypotonia can influence these contractions, and treatment may involve medications to address the underlying cause.

Step-by-step explanation:

Understanding Sudden Muscular Contractions

A term for a sudden, irrepressible, shock-like contraction of a muscle that is triggered by an event in the central nervous system (CNS) is known as a spasm or convulsion. These involuntary muscle contractions can result from a variety of causes, including neurological disorders, reactions to medications, or severe disturbances in electrolytes. The condition referred to involves an onset of sustained muscular contraction during which there is an inability to release the muscle, potentially leading to serious consequences such as respiratory paralysis if the contraction involves the chest muscles.

The underpinning mechanism of muscle contractions, in general, involves the neurotransmitter acetylcholine (ACh), which is released from the motor neuron at the neuromuscular junction. The ACh binds to receptors on the muscle fiber, leading to depolarization and the subsequent events resulting in muscle contraction. The muscle fiber will then either shorten or increase in tension, dependent upon the type of contraction occurring.

Conditions that affect muscle tone, such as hypertonia or hypotonia, might also influence the occurrence and nature of these contractions. Hypertonia is characterized by excessive muscle tone and can lead to muscle rigidity or spasticity, which are phasic increases in muscle tone. Conversely, hypotonia occurs when there is an absence of muscle tone, leading to a flaccid muscle appearance. Determining the cause of such sudden muscular contractions is essential for treatment, which may range from medications such as antihistamines or steroids to address the underlying issue.