title: Modulation of alkaline phosphatase in different organs by ascorbic acid and related compounds.
abstract: The organ-specific modulation by ascorbic acid and related compounds on alkaline phosphatase activity of calf intestinal and human placental tissues has been studied at pH 8.0 and 37 degrees C. L(+)-ascorbic acid and its isomer D(-)-ascorbic acid inhibit to a similar extent the intestinal isoenzyme and appear to be more potent modifiers than dehydro-L-(+)-ascorbic acid. In contrast, the placental isoenzyme shows an initial activation by the three chemical agents, followed by an inhibition. The inhibition is lower with L(+)-ascorbic acid and D(-)-ascorbic acid, while its catalytic activity is affected only slightly by dehydro-L-(+)ascorbic acid.
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism*; D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology*; D002417:Cattle; D003683:Dehydroascorbic Acid / Q000494:pharmacology; D005260:Female; D006801:Humans; D007422:Intestines / Q000201:enzymology; D007527:Isoenzymes / Q000378:metabolism*; D010920:Placenta / Q000201:enzymology; D011247:Pregnancy; D013237:Stereoisomerism; D013997:Time Factors
chemical_list: D007527:Isoenzymes; C005056:isoascorbic acid; D000469:Alkaline Phosphatase; D001205:Ascorbic Acid; D003683:Dehydroascorbic Acid