Neurotransmitters are chemical messengers that play a crucial role in the regulation of physiological processes and brain function. This article reviews the biosynthesis of key neurotransmitters, their functional significance, and the pathologies associated with their dysregulation. Emphasis is placed on catecholamines, serotonin, acetylcholine, and gamma-aminobutyric acid (GABA), highlighting their biochemical pathways, regulatory mechanisms, and clinical implications. Understanding the molecular mechanisms of neurotransmitter biosynthesis and function provides insights into the treatment of neurological and psychiatric disorders.

Neurotransmitters, Biosynthesis, Catecholamines, Serotonin, Acetylcholine, GABA, Neurological disorders, Psychiatric disorders.

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