Final answer:
Benzodiazepines, such as diazepam, modulate the activity of GABA receptors in the brain, which has an inhibitory, quieting effect. This action explains their use in treating anxiety and insomnia.
Step-by-step explanation:
Benzodiazepines, such as diazepam, and other anxiolytics modulate the activity of receptors for the neurotransmitter GABA (gamma-Aminobutyric acid). GABA is predominantly an inhibitory neurotransmitter in the brain which when activated through these drugs, promotes a quieting effect. This makes GABA agonists suitable for the treatment of conditions such as anxiety and insomnia.
An example of how these substances exert their effects is through the GABA-gated chloride channel. When benzodiazepines bind to this, it leads to the opening of the channel, allowing chloride ions to enter the neuron and make it less likely to fire, thereby having a depressant effect. Benzodiazepines such as diazepam work by promoting the activity of GABA receptors, enhancing their inhibitory effect on the central nervous system.