Mechanism of spinal deformity produced by pinealectomy and the role of a circadian dock of the pineal gland on developing the spine in the chick

松果体切除造成脊柱畸形的机制及松果体昼夜节律对雏鸡脊柱发育的作用

基本信息

批准号：
12640647
负责人：
HATTORI Atsuhiko
金额：
$ 2.3万
依托单位：
Tokyo Medical and Dental University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2002
项目状态：
已结题

项目摘要

Pinealectomized chickens ax known to develop scoliosis, but the mechanism underlying this phenomenon is unknown. On the other hand, the pineal gland at 1 day-old chick shows a ciicadian rhythm, however, the rhythm dumps out in accordance with aging. Therefore, we investigated the role of a arcadian dock in the pineal gland on the spinal deformity. We examined the rate of spinal deformity in the broilers that are pinealectomized at different ages. The rate of spinal deformity decreased in accordant with removal day of age. These results suggest that the Orcadian dock in the pineal gland is important to develop the spine. We conducted the next study to verify two proposed hypotheses lor the etiology of the spinal deformity: asymmetric growth cfliievertebral bone and the buckling. Tnerefore the influence of body growth on the degree of spinal deformity was investigated Piiiealectomized broilers at 1 day-old were kept under different dietary foods for 2 weeks. Tne mean degree of the spinal deformity in full, 75, and 50% diet was 50,38 and 13°, respectively. These residta show that the induction of spinal deformity in pinealectomized chicks is related to the body growth. Futhermore, the pinealectomized diiciks were sacrificed at 4 days old, and the 76 vertebra was collected and examined ossification in the anterior and posterior parts of the vertebral bone. No difference was found in ossification in the anterior part of vertebral bone, but the area of ossification in the posterior part was significantly larger (P<0.001) in the pinealectomized chicks. At present, scoliotic deformities were thought to occur as a result of causing differences in bone growth between the anterior and posterior elements of the vertebral column, and the buckling phenomenon caused by the marked increase of the body growth.

已知松果体切除的鸡会出现脊柱侧弯，但这种现象的机制尚不清楚。另一方面，1日龄雏鸡的松果体显示出蝉的节律，但随着年龄的增长，节律会逐渐消失。研究了松果体中的阿卡迪亚码头对脊柱畸形的作用我们检查了不同年龄松果体切除的肉鸡的脊柱畸形率。畸形随着去除年龄的增加而减少。这些结果表明，松果体中的奥卡迪亚码头对于脊柱的发育很重要。我们进行了下一项研究，以验证关于脊柱畸形病因学的两个假设：椎骨的不对称生长。因此，研究了身体生长对脊柱畸形程度的影响。将 1 日龄的切除肉鸡饲养在不同的日粮下 2 个月。全日粮、75%日粮和50%日粮中脊柱畸形的平均程度分别为50°、38°和13°。这些结果表明，松果体切除雏鸡的脊柱畸形的诱发与身体生长有关。 4日龄处死松果体切除的diiciks，收集76块椎骨并检查其前后部的骨化情况椎骨前部骨化没有发现差异，但松果体切除的雏鸡后部骨化面积明显更大（P<0.001），目前认为发生了脊柱侧凸畸形。由于造成脊柱前部和后部骨质生长的差异，以及身体生长明显增加而引起的屈曲现象。