Role of injection of different doses of melatonin for scoliotic deformity in the pinealectomized chickens / 中华骨科杂志

ABSTRACT

Objective To find out if different doses of melatonin have different roles in the cause or treatment of idiopathic scoliosis, and to illuminate whether melatonin can be a substitution in the treatment of pinealectomized chickens. Methods Fifty Little-Shaoxing chickens, in which pinealectomy was performed when 3-day-old, were divided into five groups. Ten served as control group, were kept in light-dark (12h 12h) cycle, 500 lx in daytime and 0-5 lx in nighttime after surgery. Ten served as M-5 group, were given 5 mg/kg (5 milligrams per kilogram of body weight) melatonin twice every day. Ten as M-10 group, given 10 mg/kg melatonin abdominally twice every day, ten as M-20 group, given 20 mg/kg melatonin twice every day, and ten as M-40 group, given 40 mg/kg melatonin twice every day. The light-dark (12h 12h) cycle was the same as control group. Radiological examinations were performed on all chicken spines for scoliosis when at 3 months old. Measured of the angle of the scoliosis was taken by Cobb's technique, and the data was analyzed by statistical software. Results Overall, there was 25 chickens developed to scoliosis in all when the chickens were 3 months. The attack rate was only 56%; this rate was consistent throughout all experimental groups. In the control group, 6 chickens had obvious scoliosis, and 5 in M-5 group, 5 in M-10 group, 4 in M-20 group, and 5 in M-40 Group. And the average Cobb's angle of control group was 26.7?. There were 23.5?, 21.7?, 24.5? and 23.2? in M-5, M-10, M-20 and M-40 respectively. There was no statistical significance in the average Cobb's angle and the incidence of scoliosis among all groups. It was determined that neither the prevalence nor the pattern of the scoliosis was affected by the therapy in any of the experimental groups. Conclusion Different dose of melatonin can't reduce the rate of scoliosis in the pinealectomized chickens, and also can't prevent the development of the experimental scoliosis. The results of this study raise doubts regarding the role of melatonin in the development of scoliosis after pinealectomy in the young chicken. Melatonin acting as a vicarious therapeutic tool in the treatment of idiopathic scoliosis is premature, deserved further research.