Nogo-A represses anatomical and synaptic plasticity in the central nervous system

Neurochemical transmission, the conduction of electrical impulses between neurons mediated by neurotransmitters, plays a vital role in various physiological processes. Autonomic drugs exert their effects by modulating neurotransmission within the autonomic nervous system. For instance, drugs such as hemicholinium block the precursor uptake necessary for synthesizing acetylcholine, an essential autonomic neurotransmitter. Following synthesis, neurotransmitters are stored in vesicles. Metyrosine...

Neuroplasticity reflects the brain's remarkable capacity to adapt and evolve, responding dynamically to learning, experiences, or injury by reorganizing its neural circuitry. This reorganization involves creating new neural connections and refining old ones through a series of biological processes that contribute to the brain's lifelong development and adaptability.

Certain drugs can affect how neurotransmitters called catecholamines, are released or taken back up in the adrenergic neuron. They can have different effects on the body's sympathetic transmission. Reserpine, a natural compound found in the Rauwolfia shrub, blocks a transporter called vesicular monoamine transporter (VMAT), which leads to a buildup of catecholamines in the cell and reduces sympathetic transmission. Another drug called guanethidine works in multiple ways, including blocking...

Drugs affecting neurotransmitter synthesis can impact the adrenergic neuron and the synthesis of neurotransmitters. For example, α-methyltyrosine and carbidopa target specific enzymes involved in catecholamine synthesis. α-methyltyrosine inhibits the enzyme tyrosine hydroxylase, which converts tyrosine into dopamine. By blocking this enzyme, α-methyltyrosine reduces dopamine production and other catecholamines. Carbidopa, on the other hand, inhibits the enzyme dopa decarboxylase, which converts...

Ligand-gated ion channels are transmembrane proteins that play a vital role in intercellular communication and functions of the nervous system. They allow the influx of ions across the membrane once the neurotransmitter binds, allowing the subsequent transmission of electrical excitation across the neurons. Other ligand-gated ion channels, like the γ-aminobutyric acid (GABA) receptor, permit anions like chloride into the cells on the binding of the GABA molecule. Their entry into the cell...

When an action potential reaches the presynaptic axon terminal, it releases neurotransmitters from the neuron into the synaptic cleft at a chemical synapse. The released neurotransmitter can be excitatory or inhibitory. The critical criteria commonly used to determine whether a molecule is a neurotransmitter at a chemical synapse are the molecule's presence in the presynaptic neuron. Second, its release is in response to strong presynaptic depolarization. And lastly, the presence of specific...