Date of Award


Degree Name

Biological Sciences


College of Science

Type of Degree


Document Type


First Advisor

Eric R. Blough

Second Advisor

David Mallory

Third Advisor

Charles Eric Arnold


How insulin resistant muscle responds to mechanical overload (MOV) is not well understood. Using immunohistochemical analysis and immunoblotting, we investigated whether Lean Zucker (LZ) and insulin resistant Obese Zucker rats (OZ) respond in a similar fashion to MOV. Five young adult (2 months old) male LZ and OZ rats were subjected to a surgical ablation of the gastrocnemius muscle and overloaded for 8 weeks. MOV-induced increases in soleus muscle mass and average fiber cross-sectional area were attenuated in OZ compared to LZ animals. This reduction in OZ muscle adaptation was associated with decreased activity / phosphorylation levels of STAT3, β-catenin and calcineurin. These data suggest that insulin resistance may decrease the ability of skeletal muscle to hypertrophy and that this impairment may be due to alterations in the ability of insulin-resistant muscle to activate STAT3, β-catenin and calcineurin signaling.


Obese syndrome.

Obesity in animals.