Pineal transplantation after pinealectomy in young chickens has no effect on the development of scoliosis

Study Design. Three experimental groups and one control group of chickens u nderwent different surgical procedures to determine the effects of pineal g land transplantation on the development of scoliosis. Objective. To determine whether transplantation of the pineal gland to the body wall musculature maintains serum melatonin levels at normal values and prevents the development of scoliosis. Summary of Background Data. Scoliosis occurs consistently after pinealectom y in young chickens. Many characteristics of this scoliosis are similar to those seen in patients with adolescent idiopathic scoliosis. It is not clea r whether the underlying mechanism is dependent on reduced levels of serum melatonin dr some other aspect of the extensive surgery. Methods. Four groups of chickens were selected: normal chickens, pinealecto mized chickens, chickens that underwent simple cutting of the pineal stark, and chickens that underwent transplantation of the pineal gland into the b ody waif. Development of scoliosis was determined from measurement of the C obb angle from weekly radiographs. Results. All of the experimental groups showed the same levels of incidence and the same patterns of scoliosis development. Serum melatonin levels wer e reduced to nearly zero in all the experimental groups for the duration of the experiment. Scoliosis developed in none of the normal chickens. Conclusions. Neither transplantation of the pineal gland into the body walt musculature nor simple cuffing of the pineal stalk was able to maintain no rmal levels of serum melatonin because both procedures reduced levels to ne arly zero. The incidence and pattern of scoliosis development in these grou ps were the same as those for the pinealectomized group. Reduction of serum melatonin levels remains a prerequisite for scoliosis development in young chickens.