Sterol metabolism in fetal, newborn, and suckled lambs and their responsiveness to dietary cholesterol after weaning. Cavender, Cary P., Stephen D. Turley, and John M. Dietschy. Departments of Internal Medicine and Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas 75235-8887
APStracts 2:0065E, 1995.
Several aspects of cholesterol metabolism were studied in lambs at six stages of development. The first three stages involved fetal lambs with gestational ages (fertilization set at -150 days) of -73 days (early fetal), -42 days (mid fetal), and -14 days (late fetal). The other groups comprised newborn (0 days), suckled (17 days), and weaned (105 days) lambs. The liver, kidney, spleen and brain actively synthesized cholesterol at all stages of development, but hepatic synthesis in the suckled lambs was markedly suppressed compared to that in their newborn and weaned counterparts. While intestinal sterol synthesis was very low in all the fetal lambs, the converse was true in the neonatal animals. The total cholesterol concentration in the liver, intestine, kidney and spleen remained relatively constant at all stages of growth, whereas in brain tissue it increased throughout development. Plasma total (TC) and low density lipoprotein-cholesterol levels (LDL-C) were lowest in the late fetal lambs, and highest in the suckled animals. The metabolic response of weaned lambs to a dietary cholesterol challenge was similar to that reported for various monogastric species.

Received 1 December 1994; accepted in final form 30 March 1995.
APS Manuscript Number E500-4.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 19 April 1995.