Fig. 4
Continuous single-dose ISO delayed C2C12 cells differentiation and myoblast fusion through altering β-AdR. a The typical image of β1-AdR and β2-AdR expressions in proliferating or differentiated C2C12 cells as detected by immunofluorescent staining. Green color indicated corresponding AdR expression in C2C12 cells; blue color indicates DAPI-labeled nuclei. b-c The differentiated C2C12 cells compared with proliferating cells have shown the increased levels of β2-AdR as determined by Western blot, but no difference in β1-AdR. α-tubulin as the internal control. *P = 0.0019 vs. proliferating C2C12 cells; n = 3. d-f The traits of increased β1-AdR and pβ2-AdR in differentiated C2C12 cells with decreased β2-AdR when exposed to the stimulation of continuous single-dose ISO were determined by Western blot. α-tubulin as the internal control. @P = 0.00014 vs. Ctrl; #P = 0.0004 vs. 10-8 M ISO; &P = 0.0002 vs. 10-7 M ISO; *P = 0.0016 vs. 10-6 M ISO; n = 3. g The typical image of myoblast fusion as determined by immunofluorescent staining of MyHC. Red color indicates MyHC; blue color indicates DAPI for nuclear labeling. h Continuous single-dose ISO decreased the myotube numbers of more than 5 myoblast fusion day 6 after C2C12 cells differentiation while increasing the myotube numbers of less than 5 myoblast fusion, the specific effects could be obviously abolished by β1-AdR inhibitor CPG-20712 (10-7 M). &P = 0.0005 vs. Ctrl; $P = 0.0012 vs. 10-5 M ISO; n = 3