RNA is easily degraded by RNAses. An efficient and non-hazardous method optimizing RNA preservation and extraction is needed. Our aim was to evaluate RNA preservation methods on murine granulation tissue from subcutaneously implanted ePTFE tubes. ePTFE tubes were placed subcutaneously in mice, removed after ten days and randomized to four RNA preservation groups. Storage in RNAlater at 4 degrees C and snap freezing in methanol/acetone yielded significantly better RNA quality than snap freezing with liquid nitrogen and storage in RNAlater at -80 degrees C. Snap freezing in liquid nitrogen failed to yield intact RNA. We recommend storage in RNAlater at 4 degrees C.