Considerations in assessing blood glucose in mice: coping with interferences of intraperitoneal injection, noise, fasting, housing and blood sampling.

Zheng, Si-Li; Wang, Xue-Lian; Wang, Pin; Chen, Jin; Miao, Chao-Yu

Background: Blood glucose levels can fluctuate for many reasons. This study is to discuss conditions in assessing blood glucose in C57BL/6J mice, providing references to help increase the success of blood glucose testing in mouse experiments. Methods: Animals were fed common chow or high-fat diet, without fasting or with a fasting duration of 6 h in the daytime or overnight before the test. During the test, animals were awake or under good anesthesia induced by intraperitoneal (IP) injection of sodium pentobarbital, interfered by a record of construction noise or not, in grouped cages or individual cages. Blood glucose measurements by glucose meters and insulin tolerance tests (ITT) were performed. Results: Both IP injection and noise independently raised blood glucose levels in conscious mice, while neither of these two interferences affected blood glucose levels in mice under good anesthesia. In an ITT, a fasting of 6 h in the daytime worked well, while an overnight fasting was at higher risk of hypoglycemia. During conscious ITT, animals housed in isolated cages were more likely to have smoothly decreased levels of blood glucose with a lower minimal value as compared to those in social cages. Blood glucose tested during different stages of blood sampling varied greatly, where values of blood collected by inferior vena cava puncture were significantly higher than those of tail-tip blood, and values of serum samples after immediate centrifugation of blood were the highest, followed by those of serum samples underwent a common clotting process of 2 h. Conclusions: Interferences of IP injection and noise can be reduced by anesthesia. 6-h fasting in the daytime is suitable for mouse ITT. Single housing works better than group housing during serial measurements of blood glucose in conscious mice. Tail-tip blood rather than serum or blood from sampling processes with big surgery invasion is recommended for blood glucose testing.

BLOOD sugar; VENA cava inferior; BLOOD sugar measurement; HIGH-fat diet; INSULIN resistance

Bulletin of the National Research Centre, 2024, Vol 48, Issue 1, p1

2522-8307

Academic Journal

10.1186/s42269-024-01287-y