griPASTA: A hacked kitchen scale-based system for quantification of grip strength in rodents

• Published in: bioRxiv
• Main Authors: Homolak, J, Virag, D, Kodvanj, I, Matak, I, A Babic Perhoc, Knezovic, A, J Osmanovic Barilar, Trkulja, Vladimir, Salkovic-Petrisic, M
• Format: Paper
• Language: English
• Published: Cold Spring Harbor Cold Spring Harbor Laboratory Press 19.10.2020
• Subjects: Animal models
• DOI: 10.1101/2020.07.23.217737

Abstract Assessment of neuromuscular function is critical for understanding pathophysiological changes related to motor system dysfunction in animal models of different diseases. Among a number of methods used for quantification of grip performance in rodents, gauge-based grip strength meters seem to provide the most reliable results, however such instruments are unaffordable by many laboratories. Here we demonstrate how to build a grip strength apparatus for rodents from scratch using a digital kitchen scale, an empty cage and a microcontroller, with both hardware and software being completely open-source to enable maximal modularity and flexibility of the instrument in concordance with the principles of open-source bioinstrumentation. Furthermore, we test the griPASTA system for assessment of increased muscular rigidity in the proof-of-concept experiment in the rat model of Parkinson’s disease induced by intrastriatal administration of 6-hydroxydopamine (6-OHDA). Finally, the importance of bioinstrumental customization is demonstrated by exploiting the ability of griPASTA to provide raw data and enable calculation of grip strength trial speed, a variable known to affect the grip strength measurements that is not standardly measured by the commercial grip strength meters. Competing Interest Statement The authors have declared no competing interest. Footnotes * The manuscript was extended and rearranged as it was originally conceived as a brief communication article. In its current form: 1) Introduction was extended 2) Materials and methods section was extended and the proof-of-concept experiment on 6-OHDA was included in the manuscript. 3) As griPASTA provides raw data the analyses were extended to include exploration of animal weight and trial speed by means of linear mixed modelling in 6-OHDA trial, as they are both known as factors affecting grip strength assessment in rodents. 4) Novel analysis algorithm was developed by IK and included in the ratPASTA R package on GitHub and CRAN. A set of functions for the semi-automatic analysis was added in the manuscript. 4) Discussion was extended and redefined with three separate subheadings. * https://github.com/janhomolak/gripasta * https://github.com/davorvr/pasta-gp * https://github.com/ikodvanj/ratPASTA