Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0262471 (
ENT
)
5,307
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Pyrimidine and purine nucleosides and their derivatives have critical functions and pharmacological applications in the brain. Nucleosides and nucleobases are precursors of nucleotides, which serve as the energy-rich currency of intermediary metabolism and as precursors of nucleic acids. Nucleosides (e.g., adenosine) and nucleotides are key signaling molecules that modulate brain function through interaction with cell surface receptors. Brain pathologies involving nucleosides and their metabolites range from epilepsy to neurodegenerative disorders and psychiatric conditions to cerebrovascular ischemia. Nucleoside analogs are used clinically in the treatment of
brain cancer
and viral infections. Nucleosides are hydrophilic molecules, and transportability across cell membranes via specialized nucleoside transporter (NT) proteins is a critical determinant of their metabolism and, for nucleoside drugs, their pharmacologic actions. In mammals, there are two types of nucleoside transport process: bidirectional equilibrative processes driven by chemical gradients, and unidirectional concentrative processes driven by sodium (and proton) electrochemical gradients. In mammals, these processes, both of which are present in brain, are mediated by members of two structurally unrelated membrane protein families (
ENT
and CNT, respectively). In this Chapter, we review current knowledge of cellular, physiological, pathophysiological and therapeutic aspects of
ENT
and CNT distribution and function in the mammalian brain, including studies with NT inhibitors and new research involving NT knockout and transgenic mice. We also describe recent progress in functional and molecular studies of
ENT
and CNT proteins, and summarize emerging evidence of other transporter families with demonstrated or potential roles in the transport of nucleosides and their derivatives in the brain.
...
PMID:Molecular biology of nucleoside transporters and their distributions and functions in the brain. 2140
