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Updated: Jul 9, 2026

A Murine Model of Muscle Training by Neuromuscular Electrical Stimulation
Published on: May 9, 2012
MMP-2, jumping exercise and nandrolone in skeletal muscle
R C Marqueti1, J Prestes, U S Stotzer
1Ciências Fisiológicas, Universidade Federal de São Carlos, São Carlos, Brazil. marqueti@gmail.com
Abstract:
Matrix metalloproteinases (MMPs) are crucial to the development and maintenance of healthy tissue. The aim of this study was to investigate MMP-2 activity in gastrocnemius, soleus, extensor digitorium longus (EDL) and tibialis anterior (TA) muscles after exercise associated with an anabolic androgenic steroid (AAS). Wistar rats were grouped into: sedentary (S); sedentary with AAS (AAS); trained without (T) and with (AAST) AAS. Exercised groups performed a 7-week water-jumping program. The exercise increased MMP-2 activity in gastrocnemius and soleus, but not in TA and EDL. The AAS treatment decreased MMP-2 activity of EDL, as compared to the S group, with no effect in gastrocnemius and soleus. The association of AAS and training restored the normal MMP activity of EDL. Training increases tissue turnover in primary motor muscles, which in turn respond differently to AAS treatment. This data may be useful for a better understanding of muscular physiology under AAS use.
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