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Monoamine oxidase released into plasma treated with the hepatotoxin allyl formate

T Obata1, Y Yamanaka

  • 1Department of Pharmacology, Oita Medical University, Japan.

Research Communications in Molecular Pathology and Pharmacology
|June 1, 1996
PubMed

Insights

Hepatotoxin exposure caused liver damage, releasing monoamine oxidase (MAO) into the plasma. This indicates mitochondrial membrane damage and altered oxidative stress markers in liver tissue.

Area of Science:

  • Biochemistry
  • Hepatology
  • Toxicology

Background:

  • Monoamine oxidase (MAO) is an enzyme crucial for neurotransmitter metabolism.
  • Liver injury can lead to the release of intracellular enzymes into circulation.
  • Oxidative stress markers like lipid peroxide (LPO) and superoxide dismutase (SOD) are indicators of cellular damage.

Purpose of the Study:

  • To investigate the release of MAO from rat liver into plasma following hepatotoxin administration.
  • To assess changes in lipid peroxide (LPO) and superoxide dismutase (SOD) activity in liver tissue after exposure to allyl formate (AF).

Main Methods:

  • Rats were pretreated with the hepatotoxin allyl formate (AF).
  • 3H-pargyline was administered to label MAO, and its levels in plasma were quantified.
  • MAO subunit molecular weight was determined using SDS-PAGE.
  • Lipid peroxide (LPO) and superoxide dismutase (SOD) levels were measured in liver tissue.

Main Results:

  • AF-pretreated rats showed a significant increase (38%) in 3H-pargyline labeled MAO in plasma (p < 0.01).
  • MAO subunits in plasma had a similar molecular weight (~60,000) to those in liver.
  • Liver tissue exhibited increased LPO levels and decreased SOD activity, indicating oxidative stress and damage.

Conclusions:

  • Allyl formate-induced liver injury leads to the release of mitochondrial monoamine oxidase into the plasma.
  • The observed changes in MAO, LPO, and SOD suggest that liver damage results from membrane disorder and oxidative stress.

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