Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085584 (encephalopathy)
 18,178 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

PALA (N-phosphonoacetyl-L-aspartate) impairs de novo pyrimidine biosynthesis by inhibiting the enzyme aspartate transcarbamylase. During cancer chemotherapy trials the drug was given by weekly intravenous infusion. Seizures developed in 9 (11%) of the first 80 patients to receive a total dose of 9 gm/m2 or more. Seven of the affected patients had structural brain lesions; they developed seizures at a lower total dose (median of 16.4 gm/m2) than the 2 patients without clinically detectable brain lesions (115 to 130 gm/m2). Reversible encephalopathy was observed in 6 (7.5%) additional patients without clinically detectable cause other than PALA. Both seizures and encephalopathy began after the second dose of PALA or later. Experiments in rats demonstrated similar delayed-onset seizures after two or three combined systemic and intracerebral doses of PALA at 4-day intervals. Concurrent administration of uridine or carbamyl aspartate prevented the development of seizures in rats, indicating that pyrimidine starvation of the central nervous system was responsible for PALA neurotoxicity.
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PMID:Neurotoxicity of the pyrimidine synthesis inhibitor N-phosphonoacetyl-L-aspartate. 712 6