Endocrine Abstracts

Urinary N-Acytyl β-D glucoseaminidase EC: 3.2.1.31 is a lysosomal enzyme which is classified in hexosaminidases group. This enzyme is found in different tissues such as, kidney, liver and spleen, but the kidney has maximum level of enzyme.

The first step was the standardization of colourimetry and flourimetry of enzyme assay. In colourimerty method para-nitrophenyl N-acetyl β-D-glucosamine is used as substrate and in flourimetry method the substrate is 4-methyl umbelliferyl N-acetyl β-D-glucosamine.

In this study the effect of incubation time, dilution of urine and substrate concentration was analysed. Between and within CV for both methods were also calculated. The enzyme activity was measured with the two methods in fifthy diabetic patients type 1 (3–30 years) and eighty diabetic patients type 2 (30–60 years) and thirty controls for any group, and its correlation with proteinuria was examined.

Mean enzyme activity of β NAG in diabetic patients type 1 and 2 (even in patients with normal proteinuria) was higher than in controls. In diabetic patients type 1, the correlation rate between urine protein and enzyme activity (β NAG) was, r=0.72 P<0.001 and in diabetic patients type 2 was r=0.70 P<0.001. We did not find any correlation between age of patients and duration of diabetes with urine enzyme activity.