Relative mRNA abundance of paired box transcription factor 7 (PAX7; (A), myogenic factor 5 (MYF5; (B), and myogenic differentiation factor 1 (MYOD; (C) from primary bovine satellite cells cultures following treatment with 2 mM putrescine (PUT), 1.5 mM spermidine (SPD) or 0.5 mM spermine (SPE). Cultures were grown to 80% confluency and treated with DMEM/3% horse serum and 2 mM PUT, 1.5 mM SPD, or 0.5 mM SPE. Abundance was measured 0, 2, 4, 8, 12, 24 and 48 h after treatment, as described in the Materials and Methods. The main effects of polyamine, time and polyamine*time in mRNA abundance were analyzed as repeated-measures. Data represent relative mRNA abundance normalized against 18S abundance and are presented as LS mean ± SEM from six separate replicates utilizing BSCs isolated BSCs isolated from at least three different animals. Differences (p < 0.05) between polyamines and the control cultures are indicated by a * at that particular time point.