Two "lab-made" devices employed as electronic Von Frey test, for animal behavioral experiments

USACH, VANINA; DONALISIO DAVID; SETTON-AVRUJ, CLARA P.

San Luis

Congreso; SAN2023 Annual Meeting; 2023

Our group is dedicated to the study of multipotent multipotent adult stem cells involvement and their effects on peripheral neuropathies induced induced by compression and trauma, analyzing morphological, functional and behavioral aspects. As regards pain analysis, there are two well standardized approximations to evaluate severity of a nerve injury. The most commonly used behavioral test of mechano sensation is the Von Frey test which consists of a set of pencil-like devices that have a filament calibrated to exert a discrete amount of force before bending. On the other hand, electronic approximations were described, , like the mouse met, the EVF 5 from Harvard apparatus, BIO -EVF 4 from Bioseb, among others. All these electronic Von Frey tests run on the same principle: a force sensor device attached to a rigid or flexible tip that registers the force during the assay. Both types have their advantages and disadvantages, for example, the filaments have issues related to long assay times before the paw withdrawal threshold (result) is obtained, and the number of filaments to be tested usually can generate some hypersensitivity on the animal if not done properly. The electronic Von Frey solves some of these problems since the measure is continuous and the force increases over time, therefore reducing the number of events before reaching the result; although at the same time discrete amount of increasing force (20 g/s) is needed to obtain correct reading. Differences aside, both approaches accomplish the same results, determining the paw withdrawal threshold to evaluate pain in rat models.The aim of this work was to present two ?lab made? devices built with commercial components. The first, an electronic VonFrey test with a robust functionality and solid accuracy, and the second, a Von Frey test with an exceeding data acquisition speed and multidirectional sensitivity that that can also be configured to evaluate electrophysiology .