Fig. 2. Immunohistochemical analysis of pRyR1Ser2840 in rat LAT and GAS muscles. (A and D) Double staining against (a) α-actinin and (b) pRyR1Ser2840 shows localizations of Z-disks (α-actinin) in close vicinity of junctional sarcoplasmic reticuli (pRyR1Ser2840) that surround t-tubuli, which are located in the transitional zone of A- and I-bands in skeletal muscles. The merged picture is demonstrated in (c). Fold changes of pRyR1Ser2840 in LAT (B) and GAS (E) muscle under 1xLevel and 1xDownhill conditions compared to CON conditions. pRyR1Ser2840 shows significantly elevated levels in both muscles after acute exercise stimulations. Representative pRyR1Ser2840 staining in LAT (C) and GAS (F) muscle under CON, 1xConc, and 1xEcc conditions. The upper panels depict the pRyR1Ser2840 pattern; the lower panel shows control slides that were incubated with 0.8% BSA instead of primary antibody. ** p<0.01, *** p<0.001. Bar in (A and D) is 5 Ám, bar in (C and F) is 50 Ám. In total, n=2000 muscle fibers were measured per intervention group.