The effects of established diabetes on the growth of the fetal liver and skin in the rat.
1. The effects of uncontrolled maternal diabetes on the growth of the whole rat fetus and its liver and skin were studied over the last 4 days of gestation. 2. Smaller fetuses, with growth-retarded livers and skins, were consistently found between 18 and 21 days in the diabetic pregnancies. 3. The smaller diabetic livers and skins (i.e. combined epidermis and dermis) possessed lower protein, RNA and DNA contents, compared with the same fetal tissues from normal pregnancies. 4. The growth retardation of the livers in diabetic fetuses was attributed to fewer normally sized hepatic cells. 5. Whilst hepatic rates of protein synthesis (measured in vivo) remained largely unchanged, these were actually increased in the skin, compared with normal control tissues. 6. These findings point to an elevated rate of protein degradation in both diabetic tissues as the most likely cause of their retarded growth.