Depolymerization of dendritic microtubules following incubation of cortical slices.

Electron microscopical examination indicated that incubation of slices of rat cerebral cortex in Krebs buffer at room temperature of 37 degrees C led to a rapid and more or less complete depolymerization of dendritic microtubules. The loss of dendritic microtubules did not appear to be a consequence of anoxia. Myelinated axons showed only a partial loss of microtubules and the microtubules of preterminal axons were unaffected by incubation. These results indicate differential labilities of axonal and dendritic microtubules under these conditions of incubation. Such an effect of the incubation of slices in Krebs buffer indicates a need for caution in the interpretation of experiments on slice preparations.