Actin immunoreactivity localizes with segregated microtubules and membraneous organelles and in the subaxolemmal region in the beta,beta'-iminodipropionitrile axon.

Using the peroxidase-antiperoxidase staining technique with monoclonal and polyclonal antibodies against actin, we found that, in beta,beta'-iminodipropionitrile (IDPN)-treated axons, actin immunoreactivity was codistributed with segregated microtubules and membranous organelles in the central region and excluded from the peripheral axoplasm occupied by neurofilaments. Actin immunoreactivity was also present in the subaxolemmal region. Fast axonal transport is localized in the central region of the IDPN axon (Papasozomenos et al., 1982a). As both microtubules and actin are present in the central region of IDPN axons, a possible role of actin in fast axonal transport warrants further investigation.