Measurement of superoxide dismutase, diamine oxidase and caeruloplasmin oxidase in the blood of thoroughbreds.

The research article discusses the development of methods to measure three specific enzymes, namely superoxide dismutase, diamine oxidase, and caeruloplasmin oxidase, in the blood of thoroughbred horses. It further investigates the correlation of these enzymes to the concentrations of their respective associated trace metals.

Methods of Measuring Specific Enzymes

• This research was prompted by a need to identify appropriate methods to measure the levels of superoxide dismutase (SOD), diamine oxidase (DAO), and caeruloplasmin oxidase in the blood of thoroughbred horses.
• The researchers developed such methods and proceeded to apply it on 178 healthy thoroughbred horses stabled in the United Kingdom.

Relationships Between Enzyme and Trace Metal Activities

• The study also sought to understand the relationships between the activities of these specific enzymes and the concentration of their associated trace metals in the blood. These trace metals include copper, zinc, and manganese.
• To measure these trace metals, the researchers employed a method known as electrothermal atomic absorption spectrophotometry.
• However, the research did not observe any significant relationships between the activities of erythrocyte SOD and the serum/whole blood copper, zinc, and manganese. Similarly, the activities of serum DAO and the concentrations of serum copper or zinc were found to be independent of each other.

Notable Findings

• The most notable finding of this study was the observed correlation between equine blood caeruloplasmin oxidase activity and serum copper concentration. Indeed, a positive correlation was found, with a score of r = 0.695 (P less than 0.001) over the normal range.
• Despite the promising findings, the deficiency or toxicity of trace metals in thoroughbreds could not be studied due to a lack of available samples.

Normal Ranges of Enzyme Activities

• The study also established the normal ranges for the activities of these enzymes in thoroughbreds, specifying units per litre for DAO and units per ml for caeruloplasmin oxidase and SOD for numerical simplicity.