Distribution of 5′-nucleotidase and gamma glutamyl transferase activities in the tissues of the horse.

This research article discusses the distribution of 5′-nucleotidase (5′-NT) and gamma glutamyl transferase activities in various tissues of horses, noting that 5′-NT activity is primarily found in lung, kidney, small intestine, mammary gland, liver, and pancreas. These activities are low in brain and muscle tissues. The study also reiterates previous findings of high gamma glutamyl transferase activity in kidney, liver, and pancreas.

Distribution of 5′-nucleotidase activity

• The study provides detailed information on the distribution of 5′-NT activity in different horse tissues. Significant levels of 5′-NT activity were found in tissue homogenates from the lungs, kidneys, small intestine, mammary gland, liver, and pancreas. Lower activity levels were recorded in brain and muscle tissues.
• The activity of 5′-NT could be visually demonstrated – a process termed histochemically – within the kidneys’ glomeruli and tubules, the sinusoidal borders of the hepatocytes (liver cells), the bile duct epithelium, and the blood vessels in all organs.

No significant difference in 5′-NT activity

• The researchers did not observe any significant difference between the 5′-NT activity in the serum and plasma of normal horses versus those suffering from a range of orthopaedic conditions. This may suggest that 5′-NT activity is not a reliable biomarker for these conditions within the horse population.

Confirmation of gamma glutamyl transferase activity

• The researchers also confirmed previous findings that gamma glutamyl transferase activity is greatest in the kidney and high in the liver and pancreas. Gamma glutamyl transferase is an enzyme involved in the transfer of amino acids across the cellular membrane and is often used as a marker for liver disease in humans and animals. Its presence in high amounts in these specific tissues corroborates previous research.

The research provides important insights into the distribution of these two enzymatic activities within horse tissues. This could potentially have significant implications for veterinary diagnostics and treatment strategies.