A gentamicin CRC using eleven different concentrations of gentamicin ranging from 1.7 ng/mL up to 100 μg/mL was tested in a FLIPR calcium assay using four CHO cell lines, each expressing a different heterodimeric NMDAR, including GluN1-GluN2A, GluN1-GluN2B, GluN1-GluN2C, and GluN1-GluN2D. The gene discussed is GRIN2B; the disease is colorectal carcinoma.