title: Induction of delta-aminolaevulinic acid synthase in leucocytes of patients on phenytoin therapy--comparison with changes in rat hepatic tissue.
abstract: 1 In rats daily phenytoin (DPH) administration resulted in an increase in hepatic cytochrome P450 content. The rise in cytochrome P450 was associated with a temporary increase in the acitvity of hepatic delta-aminolaevulinic acid (ALA) synthase. 2 In patients newly commenced on DPH anticonvulsant therapy the activity of ALA synthase in peripheral leucocytes showed a marked temporary increase during the first 10 days of therapy. 3 These findings suggest that DPH induces a haem-requiring eenzyme system in peripheral leucocytes as well as in hepatic tissue.
mesh_terms: D000624:5-Aminolevulinate Synthetase / Q000096:biosynthesis / Q000097:blood*; D000293:Adolescent; D000328:Adult; D000368:Aged; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D004790:Enzyme Induction / Q000187:drug effects; D005260:Female; D006418:Heme / Q000096:biosynthesis; D006801:Humans; D007962:Leukocytes / Q000201:enzymology*; D008099:Liver / Q000201:enzymology*; D008297:Male; D008875:Middle Aged; D010672:Phenytoin / Q000494:pharmacology* / Q000627:therapeutic use; D013997:Time Factors
chemical_list: D006418:Heme; D010672:Phenytoin; D003577:Cytochrome P-450 Enzyme System; D000624:5-Aminolevulinate Synthetase