The formation of intracristal structures induced in skeletal muscle mitochondria by high pressure

Following the application of high pressure to skeletal muscle for extended periods, intracristal structures are found in the mitochondria. In addition, electron dense granules of 70–170 nm diameter are found in the matrix of these mitochondria. In contrast, pressure-treated liver mitochondria show only large (300–400 nm) matrix granules but not the intracristal structures. Both the inner and outer mitochondrial membranes appear intact after pressure-treatment. Short periods of pressuretreatment have little effect on either the morphology of mitochondria or the pH of the tissues. It is suggested that the formation of the intracristal structures may be due to the effects of pH rather than pressure alone. This finding raises the possibility that intracristal structures may occur as a preparative artefact particularly where the tissue has undergone considerable manipulation.