Biomedical Research Models, Inc., Worcester, MA Evaluation of Blood Glucose Levels Using a Handheld Glucometer as Compared to a Clinical Chemistry Analyzer in BBDP/Wor and BBZDR/Wor Rats Barak Yahalom, Shane K. Duclos, Dennis L. Guberski, Christian W. Grant and Joan F. Flanagan Biomedical Research Models, Inc., Worcester, MA Methods Animal Models BBDP/Wor, and BBZDR/Wor as commonly used models for Type 1 and Type 2 diabetes, respectively. Chronic diabetic male rats with average duration of 12 days for BBDP/Wor and 88 days for BBZDR/Wor Introduction Historically, BRM’s facilities have been using a clinical chemistry analyzer (Analox) to determined serum glucose levels for our proprietary diabetic prone rat models. This method is an operationally time consuming process. Additionally, a whole blood glucose analysis via a handheld glucometer is a less expensive and faster method for evaluation of glycemic state. Portable glucometers have been developed and used for whole blood glucose analysis in human patients and are increasingly used to monitor diabetic animals. Moreover, their sensitivity and accuracy has been continuously improved. Therefore, we evaluated the accuracy of whole blood glucose levels measured by a handheld glucometer (Contour®) as compared to serum glucose levels (SGL) measured by Analox in BBDP/Wor and BBZDR/Wor rats. Cohorts of rats that exhibited chronic diabetes were used in this study. Type 1 diabetic BBDP/Wor rats were tested for glucose levels twice daily, prior and 3-4 hours post insulin administration. Type 2 diabetic BBZDR/Wor rats were tested once daily during the non-fed state. At each time point blood was measured by Analox and glucometer. Our data show that no statistically significant difference was detected between Analox or glucometer measurements in BBZDR/Wor rats. However, glucose levels measured by a handheld glucometer were significantly lower than the levels measured by Analox in BBDP/Wor rat. Moreover, when categorizing the readouts into subgroups according to SGL> 500 mg/dL, 200 - 500 mg/dL or < 200 mg/dL, glucose levels measured by a glucometer were statisitically significantly lower than the levels measured by Analox in all three subcategories. In summary, using a handheld glucometer for measuring blood glucose levels in BBZDR/Wor is equivalent to the use of a clinical chemistry analyzer. However, the BBDP/Wor rat’s poor hydration state may contribute to the higher glucose values measured by clinical chemistry analyzer in comparison to the values measured by a glucometer. Results Results (cont) Glucose levels measured by Analox were higher compare to handheld glucometer in type 1 diabetic rats. Glucose levels measured by Analox were equivalent when compared to handheld glucometer in type 2 diabetic rats. Figure 1: Mean Glucose Levels (mg/dL) For BBDP/Wor Rats Tested by Different Methods (Mean + SD) Figure 2: Mean Glucose Levels (mg/dL) For BBZDR/Wor Rats Tested by Different Methods (Mean + SD) A) Glucose Measurements at the High End of the Linear Range for Handheld Glucometer (SGL ≥ 500 mg/dL) Diagnosis of Diabetes Animals with a positive glycosuria and serum glucose level of >250mg/dL were considered diabetic Conclusion For our BBZDR/Wor (T2D) rat colony management and experimental studies, using a handheld glucometer for measuring whole blood glucose levels is equivalent to the use of clinical chemistry analyzer (Analox) for SGL. For our BBDP/Wor rats (T1D), using a handheld glucometer is sufficient for colony management, except for the low end of the linear range of the handheld glucometer, which due to safety reasons, additional test with clinical chemistry analyzer is recommended. For study protocols which used BGL’s in T1D rats as a study end point, a clinical chemistry analyzer is recommended. Insulin Treatment Protocol (BBDP only) PZI ® (protamine zinc insulin) was inwjected once daily subcutaneously at 0.9U/100g BW Glucose measurements Glucose levels were measured for 5 days by handheld glucometer (Contour®) for whole blood samples and Analox clinical chemistry analyzer (Model GM9D, Leominster, MA) for serum glucose levels (SGL) BBDP/Wor (n=12) Prior to and 3-4 hours post-insulin administration (n=120 blood samples) BBZDR/Wor (n=12) Once a day at the AM (n=60 samples) B) Glucose Measurements at the Mid Range of the Linear Range for Handheld Glucometer (200 mg/dL < SGL < 500 mg/dL) C) Glucose Measurements at the Low End of the Linear Range for Handheld Glucometer (SGL ≤ 200 mg/dL) Acknowledgements This work was funded by BRM, and performed by the Springfield facility technical staff. * Indicates statistical difference of p < 0.05 using T-test.