Effect of ischemic storage on endothelium in canine bone

The limits of room temperature (24 degrees C) and hypothermic (4 degrees C) storage for preservation of endothelial eccrine function were investigated with use of an ex vivo perfusion apparatus model of the cannulated canine tibia. Norepinephrine-induced contraction of smooth muscles in both the presence and absence of acetylcholine was compared, with and without selective blockade of endothelial-derived relaxing factor (EDRF). At room temperature, release of EDRF deteriorated after 24 h and was absent after 48 h of storage. At 4 degrees C, endothelial eccrine activity appeared unimpaired for as long as 72 h of storage. From 96-192 h of storage at 4 degrees C, release of EDRF was suggested, but with an attenuation of its effect on smooth muscle. At 216 and 504 h of storage at 4 degrees C, no endothelial eccrine activity was demonstrated.