Biomedical subjects

P Wilce

Publications and source records attributed to P Wilce.

23 records · Page 2Linked to original sources

PubMed1990

Acute administration of ethanol suppresses pentylenetetrazole-induced c-fos expression in rat brain.

The effect of acute ethanol administration on pentylenetetrazole-induced c-fos expression in rat brain was studied. Pentylenetetrazole induced the rapid and transient expression of c-fos mRNA in rat brain. Maximal induction at a dose of 30 mg/kg was detected within 30 min and persisted for 60 min. Thereafter c-fos gene expression decreased to control levels by 180 min. No increase in c-fos mRNA was evident at doses of pentylenetetrazole less than or equal to 20 mg/kg, whereas maximal elevation was seen at 30 to 40 mg/kg. This action was inhibited by acute ethanol treatment (blood alcohol level greater than or equal to 100 mg/dl). Acute ethanol treatment alone had no effect on c-fos gene expression.

Actins↗

PubMed1990

Ethanol and synaptosomal calcium homeostasis.

The effect of ethanol on synaptosomal calcium homeostasis was studied in the rat using the fluorescent dye, fura-2, and 45Ca uptake. The mitochondrial poison, cyanide, caused a substantial rise in intracellular free Ca2+ concentration, [Ca2+]i, over that of control synaptosomes. This rise was enhanced by ethanol. Ethanol also augmented the rise in [Ca2+]i induced by ouabain, indicating that modulation of Na(+)-Ca2+ exchange is probably not the underlying mechanism. The Ca2+ channel blockers, verapamil and La3+, also failed to inhibit the rise in [Ca2+]i caused by ethanol. Preincubation of synaptosomes with caffeine, however, caused a significant decrease in the rise of [Ca2+]i due to ethanol, suggesting that ethanol exerts effects on Ca2+ homeostasis at the level of the endoplasmic reticulum.

Animals↗

PubMed1988

Ethanol increases synaptosomal free calcium concentration.

The effect of ethanol on synaptosomal free calcium concentration [( Ca2+]i) and 45Ca2+ uptake was studied in vitro. Synaptosomes were prepared from forebrains of adult rats and incubated in the presence of ethanol 50-500 mM. [Ca2+]i determined by means of the Ca2+-sensitive dye, fura-2, was increased by ethanol in polarized and depolarized synaptosomes, whereas 45Ca2+ uptake was decreased. The results suggest that ethanol may influence neuronal calcium homeostasis by increasing rather than decreasing [Ca2+]i.

Animals↗

PubMedDate not supplied

Ethanol inhibition of brain ornithine decarboxylase activity in the postnatal rat.

The purpose of this study was to determine the relationship between ornithine decarboxylase activity (ODC; a marker for perturbed cell development), the blood alcohol level, and alcohol-induced microencephaly in the developing rat brain after binge treatment with ethanol vapour. By manipulating ethanol flow we were able to adjust vapour concentrations (24-65 mg ethanol/l air) such that an acute exposure of ethanol vapour for 3 h resulted in a range of blood alcohol levels (2.3-5.5 mg/ml). Acute studies showed that ethanol dose-dependently inhibited rat hippocampal and cerebellar ODC activity at PND4-PND10. There was a significant correlation between the blood alcohol level and degree of inhibition at all ages tested. Chronic treatment from PND4 to PND9 caused a significant decrease in both brain to body weight ratio and in hippocampal and cerebellar ODC activities at PND10. These results indicate that ethanol-induced disruption in ODC could play a significant role in ethanol's teratogenic effects during early postnatal development.

Animals↗

PubMedDate not supplied

Acetaldehyde/protein interactions: are they involved in the pathogenesis of alcoholic liver disease?

Alcohol abuse is a major cause of liver disease. While ethanol itself has been shown to be hepatotoxic, its primary metabolite acetaldehyde has also been implicated in the pathogenesis of alcoholic liver disease. The majority of ethanol metabolism occurs in the liver and high concentrations of acetaldehyde accumulate during chronic ethanol abuse. Acetaldehyde has been shown to react with many proteins in vitro, forming stable covalent adducts. These modifications can act as neoantigens and may also alter biological function. Acetaldehyde-modified proteins have been detected in the livers of ethanol-fed rats and human alcoholics. Circulating antibodies reactive with modified proteins have also been detected. A direct linkage between acetaldehyde-modified proteins, antibodies and liver damage has yet to be established, but current research should clarify the picture in the next few years.

Acetaldehyde↗