QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Trumbo, P. R. Articles by Gregory, J. F. Search for Related Content PubMed PubMed Citation Articles by Trumbo, P. R. Articles by Gregory, J. F., III

The Fate of Dietary Pyridoxine-ß-Glucoside in the Lactating Rat¹

Food Science and Human Nutrition, University of Florida, Gainesville, FL 32611

[³H]5'-O-(ß-D-glucopyranosyl) pyridoxine (PN-glucoside) and [¹⁴C]pyridoxine (PN) were orally administered to lactating rats. Milk was collected from the dam, and the stomach contents and liver were collected from the suckling pups 24 and 48 h after administration. Analysis of the isotopic ratio (³H/¹⁴C) in the milk and stomach contents indicated that the secretion of ³H in the milk was 20–25% as great as the secretion of ¹⁴C. The only labeled form of ³H and ¹⁴C in the stomach contents was pyridoxal phosphate (PLP), indicating that PN-glucoside was hydrolyzed to PN and subsequently metabolized prior to secretion by the mammary gland. The isotopic ratio in the livers of the pups was similar to that of the stomach contents. Furthermore, the relative distribution of the two isotopes among the hepatic metabolites of the pups was similar. The results of this study indicate that intact PN-glucoside is not secreted in milk, although vitamin B-6 derived from the limited hydrolysis and metabolism of PN-glucoside is delivered to the mammary gland for secretion.

KEY WORDS: • vitamin B-6 • pyridoxine • pyridoxine-ß-glucoside • milk • lactation

¹ Supported in part by National Institutes of Health Grant No. DK37481. Florida Agricultural Experimental Station Journal Series No. 9379.

² Present address: Purdue University, Dept. of Foods and Nutrition, Stone Hall, West Lafayette, IN 47907.

Manuscript received 25 July 1988. Revision accepted 26 September 1988.