G. Asins et al., DEVELOPMENTAL-CHANGES IN THE PHOSPHO(ENOL)PYRUVATE CARBOXYKINASE GENE-EXPRESSION IN SMALL-INTESTINE AND LIVER OF SUCKLING RATS, Archives of biochemistry and biophysics, 329(1), 1996, pp. 82-86
The cytosolic enzyme phospho(enol)pyruvate carboxykinase (PEPCK) is ma
rkedly expressed in the intestinal mucosa of suckling rats. The expres
sion is located in the small intestine, but there is no expression in
stomach, colon, or cecum. The expression changes with age. The mRNA le
vels at birth are very low, increase after the first lactation, reach
maximum levels between 3 and 9 days after birth, and then decrease smo
othly. At weaning, when animals begin to feed on a solid chow diet, th
e expression falls to adult levels, which are hardly detectable. Mothe
r's milk may influence the intestinal expression, since in rats weaned
at Day 18, 3 days before normal weaning the mRNA levels decreased dra
matically. mRNA levels for PEPCK in liver present a rather different d
evelopmental pattern from that of intestine, remaining high at weaning
and in adult rats. On the ninth day after birth, the mRNA levels are
the same in intestine and liver. (C) 1996 Academic Press, Inc.