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 HighWire Citing Articles via Google Scholar Google Scholar Articles by Donoghue, S. Articles by Kronfeld, D. S. Search for Related Content PubMed PubMed Citation Articles by Donoghue, S. Articles by Kronfeld, D. S.

Placental Transport of Retinol in Sheep¹

Susan Donoghue^*, Dean W. Richardson, David Sklan and D. S. Kronfeld^*

^* Sections of Nutrition Sections of Surgery, Department of Clinical Studies, University of Pennsylvania School of Veterinary Medicine, New Bolton Center, 382 W. Street Road, Kennett Square, PA 19348 Sections of Faculty of Agriculture, Hebrew University, Rehovot, Israel

Six ewes in the last trimester of pregnancy were maintained on adequate intakes of vitamin A. Indwelling catheters were implanted surgically in fetal jugular veins and carotid arteries. Three ewes and three fetal lambs received intravenous [15-³H]retinol 19 days prior to parturition, followed by sequential sampling of maternal and fetal blood. Fetal plasma retional was found to be complexed with retinol-binding protein and another protein other than prealbumin, with a total molecular weight of 30,000 to 35,000. Transfer of labeled retinol from ewe to fetus peaked at 24 hours after maternal injection. Calculation of plasma retinol transport rate from the areas under the radioactivity-time curves showed that transport in the fetus averaged 5% of that in the ewe. Approximately 260 µg of retinol was transferred daily from ewes to fetal lambs and 50 µg/day carried back to mothers. The study suggested that the carrier system of retinol in blood may not be the same in the fetal lamb as in adults, and demonstrated that retinol transfer is appreciable from fetus to ewe.

KEY WORDS: • vitamin A • fetus • placental transfer • retinol

¹ Supported by National Institutes of Health Grant HD11273 and BASF Wyandotte Corp.

Manuscript received 13 May 1982.

This article has been cited by other articles:

				S. Sankaranarayanan, M. Suarez, D. Taren, D. Genaro-Wolf, B. Duncan, K. Shrestha, N. Shrestha, and F. J. Rosales The Concentration of Free Holo-Retinol Binding Protein Is Higher in Vitamin A-Sufficient than in Deficient Nepalese Women in Late Pregnancy J. Nutr., December 1, 2005; 135(12): 2817 - 2822. [Abstract] [Full Text] [PDF]