acid-phosphatase and isoascorbic-acid

The enzyme activities, which are influenced by the vitamin C level in tissues, were measured to evaluate the vitamin C activity of erythorbic acid (ErA) in guinea pigs administered ErA. Guinea pigs were divided into two groups: animals in one group (control group) were administered 1, 5, and 100 mg/day ascorbic acid (AsA) and those in the other group (supplemented group) were administered 1, 5, 20, and 100 mg/day ErA for 16 days. At the end of the experimental period, they were sacrificed, blood was collected, and their livers were removed. The activities of liver aniline hydroxylase, of liver acid phosphatase, and of serum alkaline phosphatase, and the content of liver cytochrome P-450 were assayed. The activities of aniline hydroxylase and serum alkaline phosphatase and the content of liver cytochrome P-450 of the guinea pigs administered 1 mg ErA were lower than those of the guinea pigs administered 1 mg AsA. However, the enzyme activities and liver cytochrome P-450 content in the guinea pigs administered 5 mg or more of ErA were similar in level to those in the guinea pigs administered 5 mg AsA. These results suggested that administration of a considerably high amount of ErA to guinea pigs showed a similar vitamin C activity to that of AsA, which might suggest that vitamin C activity of ErA may be more than one-twentieth that of AsA, as has been generally believed.

Topics: Acid Phosphatase; Alkaline Phosphatase; Aniline Hydroxylase; Animals; Antioxidants; Ascorbic Acid; Cytochrome P-450 Enzyme System; Guinea Pigs; Liver; Male

The effect of erythorbic acid (ErA) administration on activities of liver aniline hydroxylase, liver acid phosphatase, and serum alkaline phosphatase, and the content of liver cytochrome P-450 was studied to determine whether or not ErA would affect the availability of ascorbic acid (AsA) in normal and AsA-deficient guinea pigs. In experiment I, changes of the enzyme activities and liver cytochrome P-450 content in the guinea pigs administered AsA and/or ErA and sacrificed on days 4, 10, 16, and 30 were examined. Moreover, in experiment II, after 16 days of depletion of AsA, the guinea pigs were administered AsA and/or ErA. These animals were sacrificed on days 0, 4, and 20 of the repletion period, after which the activities of drug metabolic enzyme and phosphatases and content of cytochrome P-450 during recovery were observed. The enzyme activities and cytochrome P-450 content of AsA-supplemented guinea pigs were similar to those of ErA-supplemented animals and also similar to those of both AsA and ErA-supplemented guinea pigs throughout the experimental period. During the repletion of the AsA-depleted guinea pigs, there were no significant differences in these enzyme activities and cytochrome P-450 content among the animals administered AsA and/or ErA. These results suggested that ErA administration may not affect the AsA availability in the guinea pigs.

Topics: Acid Phosphatase; Alkaline Phosphatase; Aniline Hydroxylase; Animals; Ascorbic Acid; Ascorbic Acid Deficiency; Cytochrome P-450 Enzyme System; Guinea Pigs; Liver; Male

The enzyme activities which depended on the ascorbic acid (AsA) tissue levels were assayed to investigate the effect of erythorbic acid (ErA) administration on the AsA availability in the guinea pigs administered 5 mg of AsA/day or 1 mg of AsA/day. The guinea pigs were given 5 mg of AsA and 1, 5, 20, 100 mg of ErA/day, or 1 mg of AsA and 1 or 20 mg of ErA/day for 16 days. The animals were sacrificed, blood was collected, and their livers were removed. The activities of liver aniline hydroxylase, liver acid phosphatase, and serum alkaline phosphatase, as well as the liver cytochrome P-450 content were measured. These enzyme activities and the liver cytochrome P-450 content of animals administered 5 mg of AsA seemed to show no change regardless of ErA supplement. Animals administered 1 mg of AsA showed different activities of liver aniline hydroxylase and liver acid phosphatase compared with those of animals administered 5 mg of AsA; however, the enzyme activities in animals administered 20 mg of ErA together with 1 mg of AsA were similar to those of the animals administered only 5 mg of AsA. These results indicated that ErA administration had no effect on the enzyme activities and the liver cytochrome P-450 content in the 5 mg AsA-supplemented animals, but administration of 20 mg of ErA was effective to maintain at normal levels the activities of liver aniline hydroxylase and liver acid phosphatase in the 1 mg AsA-supplemented animals.

Topics: Acid Phosphatase; Alkaline Phosphatase; Aniline Hydroxylase; Animals; Ascorbic Acid; Body Weight; Cytochrome P-450 Enzyme System; Guinea Pigs; Liver; Male