title: 'Acrylamide-induced' neuropathy and impairment of axonal transport of proteins. II. Abnormal accumulations of smooth endoplasmic reticulum as sites of focal retention of fast transported proteins. Electron microscope radioautographic study.
abstract: The distribution of fast axonally transported proteins was studied by electron microscope radioautography in ciliary ganglia of chickens treated or not treated with acrylamide. At 3 h after the intracerebral injection of [3H]lysine, the preganglionic axons of the untreated chickens displayed few silver grains, mainly associated with smooth endoplasmic reticulum (SER) profiles. In most axons of acrylamide-treated chickens, a similar pattern was observed, except in axons which exhibited focal and intense labeling underneath the axolemma: clusters of silver grains indeed overlayed peripheral accumulations of tubulovesicular profiles of SER, dense core vesicles and mitochondria. After impregnation with heavy metals, electron microscope observation of 1 micrometer thick sections showed a locally disorganized SER forming a complex network of tubules intermingled with vesicles and mitochondria. Such a local disorganization of the peripheral SER in the distal part of the axons, could be responsible for the focal stasis of fast transported proteins; it seems to be one of the earliest changes detectable in axons damaged by acrylamide treatment.
mesh_terms: D000178:Acrylamides / Q000633:toxicity*; D000818:Animals; D001345:Autoradiography; D001370:Axonal Transport / Q000187:drug effects*; D002645:Chickens; D004721:Endoplasmic Reticulum / Q000187:drug effects*; D005726:Ganglia, Parasympathetic / Q000187:drug effects; D008854:Microscopy, Electron; D009413:Nerve Fibers, Myelinated / Q000187:drug effects; D009419:Nerve Tissue Proteins / Q000378:metabolism*
chemical_list: D000178:Acrylamides; D009419:Nerve Tissue Proteins