Neurotransmitter

Definition

Neurotransmitters are chemical messengers that transmit signals between neurons or between neurons and other cells, such as muscle or gland cells, at the synaptic junction. They play a crucial role in the structure and function of the nervous system by facilitating communication and regulating various physiological and psychological processes.

5 Must Know Facts For Your Next Test

1. Neurotransmitters can be excitatory, inhibitory, or modulatory, influencing the likelihood of the receiving neuron firing an action potential.
2. The balance and interplay between different neurotransmitters are crucial for maintaining normal brain function and regulating various physiological processes.
3. Imbalances or dysregulation of neurotransmitter systems have been linked to various neurological and psychiatric disorders, such as depression, anxiety, and Parkinson's disease.
4. Neurotransmitters are synthesized, stored, and released from specialized vesicles within the presynaptic neuron, and their effects are terminated by reuptake or enzymatic degradation.
5. Pharmacological agents that target neurotransmitter systems, such as antidepressants and antipsychotics, are commonly used in the treatment of neurological and psychiatric conditions.

Review Questions

• Explain the role of neurotransmitters in the structure and function of the nervous system.
  • Neurotransmitters are essential for the structure and function of the nervous system as they facilitate communication between neurons and other cells. They are released at the synaptic junction, where they bind to receptors on the receiving cell, initiating a response. This process allows for the transmission of electrical signals and the regulation of various physiological and psychological processes, such as cognition, mood, and motor function. The balance and interplay between different neurotransmitter systems are crucial for maintaining normal brain function and homeostasis.
• Describe the different types of neurotransmitters and their effects on the receiving neurons.
  • Neurotransmitters can be classified as excitatory, inhibitory, or modulatory based on their effects on the receiving neuron. Excitatory neurotransmitters, such as glutamate, increase the likelihood of the receiving neuron firing an action potential, while inhibitory neurotransmitters, such as GABA, decrease the likelihood of the receiving neuron firing. Modulatory neurotransmitters, such as dopamine and serotonin, can have complex effects on the receiving neuron, influencing its sensitivity to other neurotransmitters and affecting broader neural networks. The balance and interplay between these different neurotransmitter systems are crucial for maintaining normal brain function and regulating various physiological and psychological processes.
• Analyze the implications of neurotransmitter imbalances or dysregulation in the context of neurological and psychiatric disorders.
  • Imbalances or dysregulation of neurotransmitter systems have been strongly implicated in the pathogenesis of various neurological and psychiatric disorders. For example, decreased levels of serotonin have been associated with depression, while an excess of dopamine has been linked to the positive symptoms of schizophrenia. Parkinson's disease is characterized by a depletion of dopamine-producing neurons, leading to motor dysfunction. Pharmacological agents that target neurotransmitter systems, such as antidepressants and antipsychotics, are commonly used in the treatment of these disorders, as they aim to restore the balance and proper functioning of the affected neurotransmitter systems. Understanding the role of neurotransmitters and their dysregulation is crucial for developing effective interventions and improving the management of neurological and psychiatric conditions.

Related terms

Synapse: The junction between two neurons where neurotransmitters are released and received, allowing for the transmission of signals between cells.

Action Potential: The electrical impulse that travels along the length of a neuron, triggering the release of neurotransmitters at the synaptic junction.

Receptor: Proteins located on the receiving neuron's cell membrane that bind to specific neurotransmitters, initiating a response in the receiving cell.