Repeated muscle biopsies through a single skin incision do not elicit muscle signaling, but IL-6 mRNA and STAT3 phosphorylation increase in injured muscle

To determine if muscle biopsies can be repeated using a single small (5–6 mm) skin incision without inducing immediate MAPK activation or inflammation in the noninjured areas, the phosphorylation of ERK1/2, p38-MAPK, c-Jun NH2-terminal kinases (JNKs), IκBα, IKKα, and signal transducer and activator of transcription 3 (STAT3) was examined concurrent with IL-6 mRNA in six muscle biopsies obtained from the vastus lateralis of five men. Four biopsies were obtained through the same incision (5–6 mm) from the right leg (taken at 0, 30, 123, and 126 min) and another two each from new incisions performed in the left leg (at 31 and 120 min), while the subjects rested supine. The first three biopsie…