Effect of hind limb unloading on myelination and expression of annexin V and agrin in the sensitive and mixed branches of the sciatic nerve of the mouse

Shaymardanova Gulnara Ferdinantovna, Salnikov Vadim Vladimirovich, Vasilyeva Alina Rustemovna, Gaysin Ilshat Albertovich

Data were obtained on shifts in the state of myelinated fibers of the sciatic nerve of the mouse after 30-day anti-orthostatic hanging in comparison with the control group under normal vivarium conditions. The response of the sensitive and mixed nerve branches to the experimental conditions is characterized by Transmission Electron microscopy. Changes affect both types of nerves and are qualitatively similar, consisting in a relative decrease in the number of fibers with thin myelin and the appearance of fibers with excessive myelination. The results of quantitative immunohistochemistry also indicate differences in the expression of agrin and annexin V - proteins involved in the regulation of membrane processes. Pronounced decrease in agrin expression was noted in the sensory branch, relative to increase in the mixed branch. At the same time, differences in the expression of annexin V between the functionally different sciatic nerve compartments, as well as in the comparison of control and experience, are within the error. On average, changes in the sensitive branch are more pronounced compared to the mixed branch, which may be a consequence of the advanced response of sensitive neurons to hypogravity.

Keywords:immunoelectron microscopy, myelin, agrin, annexin, sciatic nerve