Intrauterine growth retardation and development of endocrine pancreas in the experimental rat.

Intrauterine growth retardation (IUGR) was induced in rats by uterine artery ligation according to Wigglesworth. Control and growth-retarded animals were studied at days 21 and 22 of fetal life and 2 h after spontaneous birth. Fetuses with IUGR, when compared to controls, showed significantly lower glycemia and insulinemia levels. Newborn rats with IUGR had reduced glycemia levels but identical insulin values in comparison to controls. Dysmature and control animals had significantly different absolute weights of endocrine pancreas, but they had equal amounts of endocrine pancreatic tissue in proportion to their total body weight. Within the endocrine pancreas the same number of islet cells was counted in dysmature and control animals, but the animals with IUGR ended up with a reduced percentage of insulin-containing granulated B cells after birth.