Objective: To study the change of melatonin receptor mRNA expression in paravertebral muscles in adolescent idiopathic scoliosis (AIS), and analyze its relationship with the etiology of AIS.
Methods: Twenty cases with average age of (15.1 +/- 2.2) years and average Cobb angle of 56 degrees +/- 16 degrees , including 10 cases with Cobb angle > 50 degrees and 10 cases with Cobb angle <or= 50 degrees , were in AIS group. The apical vertebrae were from T(6 - 11). Twelve cases with average age of (11.6 +/- 3.2) years and average Cobb angle of 59 degrees +/- 33 degrees were in congenital scoliosis (CS) group. The apical vertebrae were from T(7 - 12). Ten cases without scoliosis were in control group. The mRNA expression of melatonin receptor subtype MT1 and MT2 were detected by RT-PCR method.
Results: The MT2 mRNA expression of paravertebral muscles on concave side was higher than that on convex side in AIS and CS groups (P < 0.05), but the MT1 mRNA expression showed no significant difference (P > 0.05). In AIS group, the ratio of MT2 mRNA expression on concave side compared with convex side in cases with Cobb angle > 50 degrees and cases with Cobb angle <or= 50 degrees showed no significant difference (P > 0.05). The MT1 and MT2 mRNA expression showed no significant difference in control group (P > 0.05).
Conclusions: The melatonin receptor expression in bilateral paravertebral muscles in AIS is asymmetric, which may be a secondary change and has no important role in the pathogenesis of AIS.