Effect of time elapsed between blood sampling and start of laboratory processing on equine PBMC JC-1 oligomer/monomer ratio. Seven horses were enrolled is this experimental setup (1, 7, 8, 10, 15, 16, 23). JC-1 oligomer/monomer ratios were calculated from mean fluorescences generated by 10,000 PBMCs (without intoxication). Delay refers to elapsed time between blood sampling and its processing into the laboratory. * Mean oligomer/monomer ratio was significantly different at 24 hours (P < 0.05).