Intraperitoneal Delivery of Iopamidol to Assess Extracellular pH of Orthotopic Pancreatic Tumor Model by CEST-MRI

Figure 6

Longitudinal changes in tumor pHe obtained by CEST-MRI using iopamidol delivered by IP in response to bicarbonate treatment in orthotopic pancreatic tumors. (a) Representative pHe maps and histograms of pHe pixel distributions in KPC961 clone 1B6 orthotopic tumors at baseline (prebicarbonate) and following bicarbonate administration by gavage 2 days later; (b) comparison of tumor pHe mean values showing a statistically significant increase in response to bicarbonate treatment; (c) delta pHe obtained by subtracting the postbicarbonate tumor pHe from baseline tumor pHe for each mouse; (d) empirical cumulative density functions (ECDF) of pHe pixel distribution in the tumors and statistical comparison using Kolmogorov–Smirnov test. The ECDF curves differ significantly with postbicarbonate showing higher pHe values.

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