Maximal Isometric Contraction in Skeletal Muscle of Endurance Trained Rats with Heart Failure

Authors

Dillon Harris, Texas A&M UniversityFollow
Jacob Kendra
Quinten Pigg
Shadi Golpasandi
Aaron Garcia
Daniela Inoue Yoshimura
Aaron Morton
Mariana Janini Gomes

Abstract

Heart failure (HF) leads to debilitating skeletal muscle dysfunction and atrophy, with exercise tolerance (ET) remaining a crucial indicator of clinical, practical, and mortality-based outcomes. To simulate these comorbidities, monocrotaline (MCT) is a pharmacological agent typically used to aid in replicating experimental models of right ventricle HF. PURPOSE: To investigate the viability of moderate-intensity aerobic training to preserve skeletal muscle function and ameliorate muscle atrophy in MCT-induced HF. METHODS: Thirty 8-week-old male Wistar rats were randomly divided into sedentary (SED) or trained groups (EX; 30min/day treadmill running sessions, 5 days/wk, for 4 weeks) at 60% intensity determined by a maximal endurance test, in which each condition received a single dose of either MCT (60 mg/kg; HF + SED; HF + EX) or equivalent saline solution (SS + SED; SS + EX). Before and after exercise training, in vivo plantar flexor maximal isometric contractions were performed to assess muscle function at 10, 60, and 120Hz. ET was assessed using a maximal endurance test before and after exercise training, respectively. Separate two-way ANOVAs were used to evaluate significance at a level of pRESULTS: Both HF + SED (p=.0016; 10.7±3min) and HF + EX (p.05). Similar differences were also found in the mass of gastrocnemius-soleus complex, wherein both HF + SED (p=.0047; 2.13±0.32g) and HF + EX (p=.0461; 2.11±0.29g) saw diminished muscle mass when compared to their parallel controls (2.66±0.15g and 2.52±0.25g for SS + SED and SS + EX, respectively). CONCLUSION: Although HF animals saw a significant reduction in skeletal muscle mass and concomitant function, endurance training remains a potentially therapeutic intervention by providing a partial protective effect on overall skeletal muscle health.

Recommended Citation

Harris, Dillon; Kendra, Jacob; Pigg, Quinten; Golpasandi, Shadi; Garcia, Aaron; Inoue Yoshimura, Daniela; Morton, Aaron; and Janini Gomes, Mariana (2024) "Maximal Isometric Contraction in Skeletal Muscle of Endurance Trained Rats with Heart Failure," International Journal of Exercise Science: Conference Proceedings: Vol. 2: Iss. 16, Article 98.
Available at: https://digitalcommons.wku.edu/ijesab/vol2/iss16/98