Neuropharmacology of Neurotransmitter Systems: Current Drugs and Their Effects on Neural and Neuroendocrine Pathways

Xiyao Qi

doi:10.62177/apjcmr.v1i1.336

Authors

Xiyao Qi The Affiliated International School of Shenzhen University

DOI:

https://doi.org/10.62177/apjcmr.v1i1.336

Keywords:

Neurotransmitter Systems, Pharmacological Interventions, Systems Neuroscience, Neuroendocrine Interactions, Translational Challenges, Personalized Medicine, Emerging Technologies

Abstract

The intricate interplay between neurotransmitter systems, neural circuits, and neuroendocrine pathways underpins brain function and dysfunction in neurological and psychiatric disorders. This review synthesizes contemporary advances in neuropharmacology, focusing on dopaminergic, serotonergic, glutamatergic, and GABAergic systems, and their roles in regulating motor control, cognition, emotion, and stress responses. Dopaminergic pathways, including the nigrostriatal, mesolimbic, and mesocortical circuits, are explored in the context of Parkinson’s disease, schizophrenia, and addiction, with emphasis on pharmacological agents such as L-DOPA, antipsychotics, and amphetamines. Serotonergic modulation through SSRIs and psychedelics is examined for its impact on mood and neuroplasticity, while glutamatergic and GABAergic systems are discussed in relation to synaptic plasticity, excitotoxicity, and therapeutic innovations like ketamine and benzodiazepines. The neuroendocrine system, particularly the hypothalamic-pituitary-adrenal (HPA) axis, is highlighted for its role in stress-related disorders and interactions with neurotransmitter networks. Despite progress, significant challenges persist, including translational gaps between preclinical models and human trials, species-specific receptor disparities, and ethical dilemmas surrounding cognitive enhancers and genetic manipulation. Emerging frontiers such as nanotechnology-enabled drug delivery, optogenetics, and gut-brain axis modulation are reviewed as transformative approaches to overcome these barriers. Personalized medicine, integrating neuroimaging biomarkers and pharmacogenomics, promises to tailor therapies to individual neural and genetic profiles, while biased agonists and closed-loop systems exemplify the shift toward circuit-specific interventions. Ethical considerations, including equitable access to advanced therapies and responsible innovation, are underscored as critical to ensuring societal benefit. By harmonizing molecular precision with systems neuroscience, this review advocates for interdisciplinary strategies to advance neuropharmacology, ultimately aiming to restore dynamic neural and neuroendocrine homeostasis in health and disease.

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