Standardization of Ex Vivo Myo-mechanical Assessment in the Rat Rectus Abdominis Muscle: Bilateral Analysis and Sex-Based Comparison to Advance Experimental Research

Standardization of Ex Vivo Myo-mechanical Assessment in the Rat Rectus Abdominis Muscle: Bilateral Analysis and Sex-Based Comparison to Advance Experimental Research | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Standardization of Ex Vivo Myo-mechanical Assessment in the Rat Rectus Abdominis Muscle: Bilateral Analysis and Sex-Based Comparison to Advance Experimental Research Juliana Ferreira Floriano, Angélica Mercia Pascon Barbosa, Lindomar Soares dos Santos, and 13 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8969029/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The fields of regenerative medicine and tissue engineering face challenges in developing affordable and reliable experimental models to study skeletal muscle regeneration and function. Although ex vivo myomechanical assessment (EMM) is a valuable tool, standardized protocols for small, flat, tendonless muscles such as the rat Rectus Abdominis Muscle (RAM) are lacking. This study aimed to develop and validate a standardized, affordable, and reproducible EMM protocol to assess the functional and myo-mechanical properties of the RAM. The methodology involved harvesting the RAM from 7 female and 10 male Sprague Dawley rats and analyzing contractile responses to electrical stimulation. Key parameters measured included Time to Peak (TTP), Rate of Force Development (RFD), and Half-Relaxation Time (HRT). Results revealed sexual dimorphism in body weight and muscle characteristics. Females showed longer TTP and significantly shorter HRT compared to males, who exhibited markedly slower relaxation properties (p < 0.001). Furthermore, Spearman correlation analysis revealed that distinct morphological factors predict muscle function across sexes. The findings highlight sex and side-specific patterns in RAM responsiveness and validate a robust protocol. This standardized EMM technique provides a reliable and reproducible method for evaluating RAM behavior, contributing significantly to preclinical research in regenerative medicine and tissue engineering. Ex vivo myo mechanical assessment Skeletal muscle myo-mechanical properties Rectus abdominis muscle Experimental standardization Regenerative medicine Full Text Additional Declarations No competing interests reported. Supplementary Files SupplementaryMaterialsfinalJMRCM.docx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8969029","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":598546876,"identity":"57c8fc42-8570-467f-a8a8-eff4d11c292c","order_by":0,"name":"Juliana Ferreira 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