Prenatal exposure to alcohol alters the Golgi apparatus of newborn rat hepatocytes: a cytochemical study.

Abstract

The effect of prenatal exposure to ethanol on the Golgi apparatus of newborn rat hepatocytes has been studied cytochemically using several trans-Golgi markers (thiamine pyrophosphatase, uridine diphosphatase, inosine diphosphatase, acid phosphatase, and 5'-nucleotidase) as well as a cis-side marker (osmium impregnation). The amount of cerium phosphate formed in the cytochemical reactions was roughly quantitated by stereologic methods. The Golgi apparatus of about 40% of the hepatocytes appeared disorganized after alcohol treatment, and in the other 60%, the electron density of reaction product deposits for all phosphatases investigated was decreased. 5'-Nucleotidase was completely absent in cisternae of Golgi apparatus of treated cells. In control cells impregnated with osmium tetroxide, reduced osmium compounds were observed in most Golgi cisternae and in nearby vesicles. In contrast, only small vesicles appeared positive in treated hepatocytes. These results suggest that prenatal alcohol exposure alters some Golgi functions. Thus, the decrease in nucleoside diphosphatase and 5'-nucleotidase cytochemical activities after ethanol exposure strongly suggests that this treatment could affect glycosylation in the Golgi apparatus of newborn rat hepatocytes.

Protein Traffic Is an Intracellular Target in Alcohol Toxicity

“…In addition, specific morphological and biochemical alcohol-induced alterations in fetal livers have also been observed, some of which are related to the GA and to the glycosylation process. Thus, prenatal alcohol exposure has been reported to induce a striking disorganization of the GA cisternae in about 40% hepatocytes, where the cytochemical activity of several trans-GA markers, including thiamine pyrophosphatase or acid phosphatase, considerably lowered [47]. In addition, these cells displayed a significant reduction in galactosyltransferase activity [48].…”

Fluorescent analogues of plasma membrane sphingolipids are sorted to different intracellular compartments in astrocytes

“…Primary cultures of rat astrocytes from 21-day-old rat foetuses were prepared from brain hemispheres as previously described [10,11]. Foetuses were obtained from rats in sterile conditions, and the cerebral hemispheres were dissected free of meninges and mechanically dissociated by pipetting 10 times with a 10-ml pipette in Dulbecco's modi-¢ed Eagle's medium (Life Technologies, Gaithersburg, MD, USA).…”

Ethanol impairs monosaccharide uptake and glycosylation in cultured rat astrocytes

“…After two 10-min rinses in 0.1% BSA-Tris buffer and a rinse in redistilled water, the sections were air-dried and finally counterstained with uranyl acetate and lead citrate (Renau-Piqueras et al 1989;Miñana et al 2000). Quantitative analysis of gold particle distribution on Golgi apparatus areas was carried out using stereological methods (Renau-Piqueras et al 1987, 1997.…”

“…Glial cells are also sensitive to alcohol, suggesting that perturbations in the neuron-glia interactions account for the alcohol-induced developmental defects of the brain (Guerri and RenauPiqueras 1997;Renau-Piqueras et al 1998;Guerri et al 2001). In addition, chronic alcohol consumption and prenatal alcohol exposure alters the glycosylation process in rat hepatocytes, neurons and astroglial cells (Vallés et al 1994;Renau-Piqueras et al 1987, 1997Kim and Druse 1996;Miñana et al 2000). This may inhibit or delay the intracellular transport of nascent glycoproteins and glycolipids in the cell or else alter the expression of membrane proteins.…”