Histological Changes in the Placenta Induced by Maternal Alcohol Consumption in the Rat

Abstract

To investigate the placental enlargement which accompanies maternal alcohol consumption during pregnancy, Sprague-Dawley rats were given 20% ethanol for 4 weeks prior to mating and 30% ethanol throughout gestation. Pair-fed controls received an isocaloric amount of corn starch and chow, with water ad libitum, and ad libitum controls received rat chow and water. On days 17, 18, 19 and 20 of gestation, placentas were removed for histological observation. On days 18–20, the placentas of alcohol-fed rats weighed significantly more than did those of controls, although there was no difference in weight on day 17. Giant cells in the basal zone were significantly increased in number and size in alcohol-fed rats compared to controls. Trophoblastic cells in the basal zone were significantly larger in the alcohol group than in the control groups except on day 17. The maternal blood channels in the labyrinth were wider and more filled with blood corpuscles in the alcohol group than in either control group. It is concluded that the increased weight of the placenta may be largely due to the stagnated maternal blood cells in the labyrinthine blood channels and also to the increased number and size of giant cells and the enlarged trophoblastic cells in the basal zone.

The effects of alcohol on rat placenta

“…The increases of placental index values of rats in P1 and P5 groups was due to the increase of placental weight in rats exposed to alcohol. These findings are consistent with the results of Eguchi et al 5 and Gordon et al 2 We supposed that this may be attributed to placental changes related to tissue damage such as hyperplasia hemorrhage and disruption of labyrinth and repair. Fibrin deposition, inflammation, fibroblast proliferation and ECM synthesis occurs during tissue damage and repair.…”

“…There are many studies describing the effects of alcohol on placental function and fetus growth. [5][6][7][8] However, data regarding ECM and growth factors of placenta after alcohol exposure are rather rare. This lack of information stimulated the present study to define the changes in placental extracellular matrix components and growth factors caused by alcohol consumption in rats.…”

Long‐term alcohol exposure prior to conception results in lower fetal body weights

“…In the present study, however, both maternal body weights and food consumption did not seem to be significantly affected by the alcohol treatment and therefore it is unlikely that the embryos were affected by changes in the status of maternal nutrition. Long-term exposure to alcohol prior to and throughout gestation affects the structure and size of the placenta (Amankwah and Kaufmann, 1984;Padmanabhan, 1985;Eguchi et al, 1989;Jollie, 1990). Such changes in placental structure may affect the transport of nutrients from the mother to the fetus (Lin, 1981;Gordon et al, 1985;Fisher et al, 1986;Snyder et al, 1986).…”

Histopathological Effect of Ketoconazole on Rat Placenta

“…Maternal hemorrhage [3], uterine vessel ligation [4], carbon monoxide exposure [18], and indomethacin treatment [27] can also elicit placental hypertrophy to facilitate compensatory recovery of fetal-growth retardation. In addition, ethanol-induced placental hypertrophy in rats might be an adaptive response to meet placental damage and repair such as hemorrhage, stagnated maternal blood, fibrin deposition and inflammation in the labyrinth zone [1,10]. Estrogen and progesterone are both essential for the initiation and maintenance of pregnancy and closely related to placental growth.…”

“…Placental hypertrophy is also detected in the intact uterus with less than six fetuses in rats [7]. Experimentally, placental hypertrophy is induced by a reduction in the number of corpora lutea [15], ovariectomy with estrogen and progesterone treatment [6], and exposure to some chemicals, such as ethanol [1,10], indomethacin [27], methylhydrazine [13], etc.…”