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Veterans Administration Medical Center, Bay Pines, FL 33504; Department of Chemistry, University of South Florida, Tampa, FL 33612; and School of Dentistry, Institute of Dental Research, University of Alabama, Birmingham, AL 35294
The effect of feeding 0.25% ethionine for 310 weeks to male and female rats on urinary and tissue ascorbate contents were studied. The concentrations of ascorbic acid in the urine, blood, liver and adrenals were significantly reduced in the rats receiving ethionine as compared to those receiving stock diet. This decrease was not apparently due to feed intake, not reversed by supplementation of methionine, but can be partially restored by removing ethionine from stock diet. The response to trichloro-2-methyl-2-propanol stimulation of urinary ascorbic acid was considerably suppressed by ethionine administration. In vitro the enzymatic synthesis of the vitamin from glucuronolactone by liver homogenate of ethionine-fed rats was significantly decreased from that of stock diet-fed controls. These results indicate that ethionine reduces the capacity to synthesize ascorbate which, in turn, causes a decrease of ascorbic acid contents in the urine, blood, liver and adrenals.
KEY WORDS: ethionine ascorbic acid
1 Supported by the Veterans Administration.
Manuscript received 9 July 1980.