(A,B) The electron micrographs show areas of contact between a mitochondrion and T-tubules. (C). Intermitochondrial contact. Inset shows the ultrastructural organization of the contact. Arrowheads show mitochondrial cristae. IMFM, intermyofibrillar mitochondrion; jSR, junctional SR; M, mitochondrion; TT, T-tubules; zSR, z-tubules of the SR; Z, Z line (Z disk); black arrows show RyRs; white arrows show structures connecting IMFM and jSR. Adapted from Parfenov et al., 2006.