title: The inhibitory effect of xanthine derivatives on alkaline phosphatase in the rat brain.
abstract: Histochemical and biochemical studies were carried out on the inhibition of alkaline phosphatase (A1-P) activity in rat cerebral cortex with various methylxanthine derivatives. The histochemical study revealed that A1-P activity was completely inhibited with 2 mM theophylline or aminophylline, only slightly inhibited with 5 mM of xanthine, and no way inhibited even with 5 mM of diprophylline or caffeine. The biochemical study showed that A1-P activity was markedly inhibited by 1 mM theophylline, to 36% of the control value, and equally markedly by 1 mM aminophylline to 26% of the control value. It was only inhibited to 99% of the control value even by 5 mM diprophylline and conversely slightly activated, to 110% of the control value, by caffeine. The relationship between the pharmacological activities of methylxanthine derivatives and A1-P was studied, and the biological role of A1-P in the central nervous system was also discussed.
mesh_terms: D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000469:Alkaline Phosphatase / Q000378:metabolism*; D000628:Aminophylline / Q000494:pharmacology; D000818:Animals; D002110:Caffeine / Q000494:pharmacology; D002540:Cerebral Cortex / Q000187:drug effects / Q000201:enzymology* / Q000648:ultrastructure; D005260:Female; D006651:Histocytochemistry; D008297:Male; D051381:Rats; D013574:Synaptosomes / Q000187:drug effects / Q000201:enzymology; D013806:Theophylline / Q000494:pharmacology; D014970:Xanthines / Q000494:pharmacology*
chemical_list: D014970:Xanthines; D000628:Aminophylline; D002110:Caffeine; D013806:Theophylline; D000469:Alkaline Phosphatase; D015056:1-Methyl-3-isobutylxanthine