Byrd K E, Sukay M J, Dieterle M W, Yang L, Marting T C, Teomim D, Domb A J
Department of Anatomy, Indiana University School of Medicine, Indianapolis 46202-5120, USA.
J Dent Res. 1997 Aug;76(8):1437-52. doi: 10.1177/00220345970760080601.
The sequelae of sustained, in vivo delivery of two important neurotransmitter substances, glutamate and thyrotropin-releasing hormone (TRH), upon craniofacial growth and development have previously not been investigated. Our purpose was to document and compare the relative effects of glutamate and TRH microspheres stereotactically placed in proximity to trigeminal motoneurons within the trigeminal motor nucleus. The following null hypotheses were tested: (1) TRH microspheres in proximity to trigeminal motoneurons have no significant effect upon the craniofacial skeleton, and (2) there are no significant differences between the relative effects of chronic, long-term delivery of glutamate and TRH upon the neuromusculoskeletal system of growing rats. Forty male Sprague-Dawley rats were divided into 4 experimental groups (glutamate microspheres, TRH microspheres, blank microspheres, sham surgeries) and underwent stereotactic neurosurgery at 35 days; 5 rats of each group were killed at 14 and 21 days for data collection. Histology revealed that implants were clustered in the pontine reticular formation, close to the ventrolateral tegmental nucleus. Both glutamate and TRH rats had implant-side deviation of their facial skeleton and snout regions; 4 x 2 ANOVA and post hoc t-tests revealed significant (P < or = 0.05, 0.01) differences between groups and sides for motoneuron count, muscle weight, and osteometric data. TRH rats also demonstrated larger implant-side TMJ discs and mandibular fossae in comparison with the other groups. The stated null hypotheses were therefore rejected.
此前尚未研究过两种重要神经递质物质——谷氨酸和促甲状腺激素释放激素（TRH）在体内持续释放对颅面生长发育的后遗症。我们的目的是记录并比较立体定向放置在三叉神经运动核内靠近三叉神经运动神经元处的谷氨酸和TRH微球的相对作用。我们检验了以下零假设：（1）靠近三叉神经运动神经元的TRH微球对颅面骨骼没有显著影响；（2）长期持续释放谷氨酸和TRH对生长中大鼠神经肌肉骨骼系统的相对作用之间没有显著差异。40只雄性Sprague-Dawley大鼠被分为4个实验组（谷氨酸微球组、TRH微球组、空白微球组、假手术组），并在35日龄时接受立体定向神经外科手术；每组5只大鼠在14天和21天时处死以收集数据。组织学检查显示植入物聚集在脑桥网状结构中，靠近腹外侧被盖核。谷氨酸组和TRH组大鼠的面部骨骼和口鼻区域均出现植入侧偏斜；4×2方差分析和事后t检验显示，在运动神经元计数、肌肉重量和骨测量数据方面，组间和侧间存在显著（P≤0.05，0.01）差异。与其他组相比，TRH组大鼠植入侧的颞下颌关节盘和下颌窝也更大。因此，上述零假设被拒绝。
