| Objective: To determine whether the pineal gland remains functional after it' pedicle disrupted in young chickens and the role of melatonin in the pathogenesis of chickens scoliosis by observing the melatonin changes following the surgery and it'relation to scoliosis.Methods:1.50 white leghorn chickens were kept in light-dark(12h:12h) cycle.Three groups of chickens were selected:normal chickens(n=10),pincalectomized chickens (n=20),chickens that underwent disrupting of the pineal pedicle(n=20).2. All surgery was performed 3 days after hatching.Development of scoliosis was determined from measurement of the Cobb angle from radiographs at weekly intervals beginning 2 week and continuing until 4 weeks after surgery and at 3 month after surgery finally.When the chickens 5-week-old,their serum were collected and analyzed with R1A kit for melatonin.Results: l.Scoliosis developed in none of the chickens in the control group.In contrast,scoliosis developed in 25%, 35%, 40%, 45%, 45% of the pinealectomy group during the experimental period respectively and in 20%, 35%, 50%, 50%, 55% of the pineal pedicle disrupted group during the experimental period respectively.There were no significant differences in the incidence of scoliosis between the experimental groups at any time during the experimental period.However,the incidence of scoliosis in both of the experimental groups was always significantly higher than in the control group.2. During the experimental period,the average Cobb angles for the pinealectomy group (11.40°±1.67,13.86°±4.10,20.13°±7.74,23.78°±9.50,32.67°±17.23) and th pineal pedicle disrupted group(11.75°±2.36, 14.71°±4.23, 20.10°±7.79, 26.80 °±10.70, 34.09°±19.63) did not differ significantly from each other. 3.1n the pinealectomy group 3/9 of the curves were classified as progressive, as compared with4/11 in the pineal pedicle dirupted group. There also were no significant difference found in the proportion of progressive curves between the two experimental groups.4.No significant different were found in serum melatonin levels between the pineal pedicle disrupted and control groups either during the daytime, when melatonin levels were low, or during the nighttime, when melatonin levels were high(58.77pg/ml ±8.44 and 248.47pg/ml±27.21, respectively, for the pineal pedicle disrupted group; 57.25pg/ml±7.43 and 257.92pg/ml±26.09,respectively,for the control group).lt was very low level,daytime and nighttime(60.05pg/ml ±5.48 and 55.09pg/ml±8.35)in pinealectomy group.Conclusions: 1. Both pinealectomy and disrupting of the pineal pedicle was able to induce scoliosis in chickens. The incidence and pattern of scoliosis development in the two groups were the same.2. Disrupting of the pineal pedicle was able to maintain normal levels of serum melatonin, but was not able ot prevent the production and development of scoliosis in chickens. 3. The pathogenesis in chicken scoliosis is not via low level melatonin.Dong Ge (Orthopaedics) Directed by Yougu Hu (Prof.)...
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