Objective: The aim of this study was to identify whether one side of the apex of the scoliotic curve showed greater muscular abnormalities than the other. This investigation sought to compare directly the expression and localization of Calmodulin (CaM) and nNOS of the thoracic spinal musculature on convex side with those on the concave side in the scoliosis patients attending for spinal surgery.
Methods: The patient group comprised 8 females and 2 males, scheduled for spinal surgery, in whom the apex of the scoliotic curve arose between T6 and T11. Muscle biopsies were taken bilaterally during surgery from the superficial multifidus muscle at the apex of the curve between the 6th and 11th thoracic vertebral levels. Part of the tissue was fixed in Formalin and stained with hematoxylin and eosin; the remaining tissue was snap frozen and processed for immunohistochemistry and western blot. The following antibodies were used for the immunohistochemistry at dilutions optimized in preliminary experiments. Goat polyclonal anti-human-CaM and mouse monoclonal anti-human-nNOS were used as primary antibodies. CaM and nNOS were detected by immunohistochemical method and Western-blot. Western blotting was done with antibodies to CaM.
Results: Compared with control muscle and the muscle on the concave side of the scoliotic curve, A significant decrease in CaM and nNOS was found on the convex side of paraspinal muscle from idiopathic scoliosis patients, Western blotting with an CaM antibody and nNOS antibody shows that there are more CaM and nNOS protein in the concave side of paraspinal muscle in these patients with adolescent idiopathic scoliosis than in the convex side.
Conclusion: This asymmetry of CaM and nNOS in the paraspinal muscle may play a role in the pathogenensis of IS.