Various microtubular patterns in dorsal root ganglia (DRG) in pyridoxine neurotoxicity

Abstract

The term “microtubule” (MT) has been ascribed to a complex group of subcellular structures deploying at least two common characteristics: a hollow cylindrical shape and a diameter of less than 30 nm. Some authors, however, regard MT as composed of tubulin with well known roles in the organization of the cytoskeleton and different cellular functions such as secretion, mitosis, and motion. In alteration of the neuronal cytoskeletal organization in neurotoxicity, their tubulin composition has usually been unquestioned. Recently observed unusual MT aggregation patterns in pyridoxine neurotoxicity definitely raised questions as to the composition of some of the groups of microtubules which fulfill the general definition. At least three different patterns of MT aggregations were seen in neuronal cytons of DRG of dogs treated with high doses of pyridoxine.The large MT aggregates made up of numerous superimposed sheets of MT in parallel arrays and having different orientation in close proximity to ribosomes and membranes of rough endoplasmic reticulum (RER) have already been reported.