Ultima gold scintillation solution

For evaluating carrier-mediated glucose uptake, mice were injected with OTP at +24 h after 4.3 Gy TBI (3.2 Gy/min) and sacrificed 48 h later. Apical transport of glucose was measured in vitro by incubating sleeves of intact proximal jejunum segments with ¹⁴C D-glucose and ³H L-glucose tracer to correct for carrier-independent D-glucose absorption (28 (link)). Briefly, jejunum segments were externalized and two 1 cm sleeves were secured by silk ligatures onto stainless steel rods. The sleeves were kept in cold Ringer’s solution (~4°C) aerated with 95% O₂/5% CO₂ during and after the mounting. Measurement of glucose uptake began 4 min after the sleeves were exposed to 37°C Ringer’s solution followed by a 2 min incubation of the sleeves in uptake solution (Ringer’s solution with 2 μM solution of the tracers). After the incubation, tissues were rinsed for 20 s in cold Ringer’s solution, blotted, weighed and dissolved using Solvable^™ solution (PerkinElmer^® Inc., Waltham, MA). Radioactivity taken up into the tissue was counted in Ultima Gold^™ scintillation solution (Perkin-Elmer). Rates of glucose uptake (pM/min) were calculated and normalized to wet tissue weight.