Evaluation of a technique for measurement of gamma-glutamyltranspeptidase in equine urine.

The research presents an analysis of the gamma-glutamyltranspeptidase (GGT) activity in horse urine using an assay specifically developed for serum usage. The tool proves reproducible and illustrates a lower enzyme activity in maintained samples at varying temperatures.

Analysis of Gamma-Glutamyltranspeptidase Activity

• The researchers analyzed the GGT enzyme’s activity in equine urine using an assay built initially for serum. Their results depict the assay’s successful reproduction.
• They tested the activity of the enzyme in samples, using gradual dilution of the GGT enzyme with horse urine. Within the activity range of 21 IU/L and 407 IU/L, the enzyme activity maintained linearity.

Comparison of Exogenous GGT Behaviour

• The researchers compared how the GGT enzyme, added externally, behaved in horse urine and serum.
• The outcomes indicated that the enzyme had similar behaviour in both fluids. Consequently, the method used for serum can be replicated for analyzing urine markers.

Effect of Storage on GGT Activity

• The study examined the effects of storing serum and urine samples at -20, 4, and 25 C degrees for 24 or 72 hours on GGT activity.
• The results show a declining trend in enzyme activity at all recorded temperatures and time periods. This decrease was highest and varied the most at -20°C.

GGT and Creatinine Ratio Stability

• The urine GGT: urine creatinine ratio was determined using urinary samples collected over 24 hours.
• Despite notable variances in urine GGT enzyme activity and creatinine concentration, the ratio was found to remain constant.
• The ratio was also calculated from arbitrary urine samples taken from 27 clinically healthy adult horses, where the mean was found to be 10.52 with a standard deviation of +/- 4.78.

Overall, the research identifies a new approach for measuring GGT activity within horse urine, potentially aiding diagnostic procedures for urinary diseases. It also suggests the need for thorough consideration while storing samples for the testing process.