Fig. 3. Increase in cell metabolites with the GHRP-6-biotin conjugate in C2C12 myocytes. Fully differentiated C2C12 myocytes were treated with 100 μM GHRP-6-biotin conjugates. Intracellular energy metabolites, ATP (A) and lactate (B) were measured in whole-cell lysates. Creatine kinase activity (C) and lactate dehydrogenase activity (D) were also assessed. (E) Expression ratio of alpha-actin vs. beta-actin was measured by immunoblot. Lower panel; densitometric analysis result. All data are shown as means ± SE. t-test. **P ＜ 0.01.